It's amazing what you can own when you don't have a pesky $200 tax to pay.
Searcher, since you're not worried about the full-auto conversion, you only need to add a compensator and a forward grip. Lots of comps out there in 38 caliber. I bought one from EGW's online auction. The forward grip mounts like the Weigand style scope mount -- drill and tap the dust cover in front of the trigger guard (typically either 8 or 10 screws). Since your copy is non-functional, you don't have to worry about cutting off the screws inside the dust cover to avoid interference with the recoil spring.
The extended magazines are $15 at the gun show. Or $12 if you bargain well.