Well there doesnt seem to be many options for the smith and wesson TRR8. Looking for a leather holster.

They are N frames, right? Wouldn't a holster for Mod 27, 25, 29, etc... work?

They are N frames, but the barrel design is unique......but that could be meaningless.

Thats the hard part is that rail on the bottom.

Well then, try Simply Rugged Holsters in Prescott Arizona.  Rob make great stuff and will make sure you get a good fit.

Check out the DIY kydex thread and see if one of those guys can help you out. I know some of them do it commercially. Or, if you want to go more conventional with leather, you'll probably still have to go custom. I've googled pics of the TRR8 recently (it's on my want list) and there's some kydex and leather holsters in some of them. Maybe you could track down who made them.

https://www.ar15.com/forums/t_10_17/628104_Do-it-yourself-Kydex----.html&page=81