looking to upgrade the exhaust but cant find anything on tr 3.5l v6s. its a sedan

TRs came with 2.6 I4 only and KRs came with 3.0 V6 only. None came with 3.5 V6. Either way, not much out there except custom made ones. I did get a TF 3.0 V6 front pipes fitted to my old Verada V6XI. That was purely to have a smoother flow where the front and rear banks met (nice smooth Y join instead of a T join).