JRZ Front Disc Caliper rebuild & Interchane with Wilwoods?

i have a set of the old JRZ front brakes on my hemi Belvedere and I need to rebuild one side with new o rings and pistons.These are the brake setup with the red billet hubs shown in the picture.
Where can I find replacement parts for them.They havent been made for quite some time. Wilwood pads interchange but dont know part # for 4 piston calipers and 10" rotors with 5 bolts and .350 thickness solid rotor.

http://i117.photobucket.com/albums/o69/SUPERSTOCKRACER/65hemiatlebanonvalley42410PIC3.jpg

need to get one piston in,its hyperextended out of the caliper?
it wont go in,cant get it to budge even with pry bar and screwdrivers.
looks like i'm going to split the caliper and go in fron the inside, i bet the o ring is caught up on the piston somehow.

You need to pull them completely apart. hone caliper puck holes and completely clean and clear all fluid passages. Strange Engineering rebuild kit is usually fits/interchanges. Or NAPA carries a variety of hydraulic O-rings and copper washers. Be sure to do both sides as the other side will fail if not rebuilt as well. They will be better than new when rebuilt.