Found these suckers for $6, claims it can clone an RF remote's codes:
http://www.dinodirect.com/12V-Sell-RF-Keyless-Entry-Wireless-Remote-Control-AK-RD088.html?cur=AUD&AFFID=74
The main caveats being
- it's for fixed-code, not rolling; I've tried searcing the site (using google site:aussiemagna.com for more complete results) but found no mention of the code style used in the stock remote
- frequency etc is: 315/433Mhz, SAW frequency stabilization. Haven't found any info on what the stock remote uses.

This is for a TL, so the most common remote style (green/red/grey).
I've found a few new ones for about $70 shipped, but if one of these'll work, I can get a couple and have quite a bit of change left over (only got one remote with the car).

I think (and hope) the Magna would use a rolling code. Haven't heard of a car to use fixed code, only older garage doors used it.

For $6 give it a go! I'd be very interested in this also as I need a new remote too and genuine price is just ridiculous.

You'd think there'd be veritable shiploads of old remotes lying around, but even second-hand ones are going for $70+ on ebay.
Might have to order one "for shits'n'giggles", unless someone posts a definitive answer. I've read posts elsewhere that claimed the code wasn't rolling, but don't give the sources much credence.

I've got a Remocon programmable remote that I use for my garage door (old school non rolling code) and wanted to see if it would work on the TE, it did only once straight after copying the car remote, so once the code rolled it no longer worked.

Even if the code was rolling it would have to know the algorithm that Mitsubishi uses for the Magna so it could be programmed, the remote wouldn't have the processing power to analyse the next 5 codes and decipher the algorithm from there.

I guess if the manufacturers hadn't gone to rolling code and with technology these days someone would just have to stand near you when you locked your car and then they'd have no issues getting into your car after you'd walked away.

So we reckon the code's definitely rolling?

The afore-mentioned "posts elsewhere" claimed that they knew of consistent instances where late-model (TL-TW) magna remotes opened adjacent magnas inadvertantly, or the owners came back to their car to find the boot popped from someone else using their boot remote. Personally I think it was a load of shit designed as a troll, but who knows.
Maybe next meet someone has, everyone try their remotes and see how many cars open!

If they roll then the roll together as I have on many occasions tested various remotes and had several cars here with 1 remote programmed into several cars at once and they will all lock and unlock together. I do this more for convenience, when cars are parked outside I lock them all, is just easy to hit 1 button to get them all to lock before I go home lol

Let us know how you go with these.

I wonder what the coding instructions are, page says nothing about it...

Just ordered one, so we'll see how it goes when it turns up.
From the pictures, I'd say the "learning" function is only at close range, so the ability for someone to hack it to "listen" for someone using a remote and gain access to that car would most likely be quite remote (pun not intended).

Dingers, Here's some Chinglish instructions that supposedly match this remote:

Clear The data:

Press the [unlock button] and [lock button] at the same time ,and keeping ,not loose, until the
indicator light flashes three times, and this time, keep pressing the [Lock button ],only to release
the unlock button, and within five seconds press [unlock button] three times slower to complete
the removal. after removed, light will be blinking.

Learning data:
Put the cleared remote control to the source remote control close face to face, firstly press the first
button of the source remote control, then press the remote control corresponding button ,until the
remote indicator blinking, that is a copy of the completion of this button. Other button operation
mode of is as same as this.

Recovery:
If you want to recovery the data ,which you were mistake cleared just now, please pressing the
other two buttons (the button is not the lock button also not the unlock button ) at the same time
not loose, until the indicator light flashes, then the remote control back to work.

Sleep:
Any one or more of the button is press and hold down after 15 seconds , the remote control will
stop working in order to save power.

PS. Worst case scenario, looks like you can get a matching receiver, so you can trigger shit:
http://www.dinodirect.com/DC-12V-Wireless-Remote-Control-Switch-AK-RK04S-12-currency-AUD.html
Could hook that into your door lock, or use it for whatever takes your fancy. If the remote doesn't work with a magna, that is.

Interesting... let us know how it goes