Seat size in L&R Rubicon, 17 or 17.5

Hello, anyone familiar with this saddle. I ride either a 17 or 17.5 and wondering what size I would need in this saddle.
I have a 17" Jeffries Elite that is a good fit, would the Rubicon be similar? Thanks, I am 5.5", 126 lb.

I think I just answered you in an email to Trumbull but the saddles ride slightly small in the seat and the knee pad has a very full feeling which will also influence how you feel in the saddle. It is a hoop tree versus the A shaped tree and will also feel wider in the twist and certainly fit the horse differently.