Modified handle for Walther GSP with grip screws on the sides.
Large and Medium size - shelf fits both.
The shelf requires an M6x20 (max 24mm) HEX bolt, nut, and washer.

For left-handed, just mirror. I tested that it fits mirrored.

Works great in PLA and especially wood PLA

I tried printing in file orientation and upside down - both work, but you have other places to clean up from supports.