Caspians are great guns, but you gotta know what you’re getting into, there are 3 generations of frames
1st gen, large frame opening under the grips and were prone to cracking, caspian and other gunsmith fixed it by welding reinforcement plates in the weak areas, the dust cover is standard 1911 thickness, so it can be a bit thin for mounting single sided optic. Easiest way to ID is 1st gen frames have a rounded trigger guard
2nd gen, square trigger guard, the frame opening is solid with 2 holes on each side, dust cover is still thin
3rd gen, square trigger guard, thick dust cover similar to a sti
aftermarket part are almost nonexistent, no one I know of makes magwells anymore, or triggers
mags can be a issue, the original mags with the satin nickel finish are great, I’m still running a few that have been in constant use since 1994 and have outlived 2 open guns, they look like they were dragged behind a moving car, but still work perfectly
mbx mags are good and pricey, and not all ways in stock
tangfogilio large frame mags and be modified to use in the caspian, but base pads must be modified also