Hm, after searching I also have come up empty on Great Ape files. I know they exist, but it looks like they don't offer them anymore for whatever reason.
I have some pretty close vambraces you can download for free here: Boba Fett Vambraces, Rearmored / Fresh version (Mandalorian) / ROTJ by Camburu
Be wary of the sizing. I have yet to go back and fix these but the left prints a little large in my experience.
I created the master model for the knees in the CRL (meaning they are screen accurate and approvable) and sell them as 3d prints here.
I also created a free model of his sidearm: Boba Fett blaster pistol (Mandalorian Season 2) by Camburu
The helmet I used was this one: Boba Fett/Mandalorian Helmet Replica 1:1 by ChrisThePropGuy
Can't guarantee perfect accuracy but looks damn good to me.
Anyway hope this helps get you started! Happy to help with any questions. My costume is still a work in progress but nearing completion after 2 years.
