This is a map of the project STL files. I think that this will greatly facilitate the selection of appropriate files for printing.
STL files with the "ht_" prefix are specially prepared templates to facilitate drilling holes in aluminum profiles in the right places. Theoretically, it is not necessary to print them, but without them, drilling holes can take much longer.
If you live in Germany, instead of picatinny_rail_laser you should print special german_laser_mount for a regular 15x68 mm round laser. All because in this country a laser intended for weapons mounted on a standard 11 or 22 mm rail is illegal. You need also 2 pieces M3x10 mm screws and 2 pieces M3 nuts for this adapter. Half of the spring from the clicky pen is also necessary to adjust the aiming.
If you don't like the finger draw_holder, you can print a draw_limiter instead (it is also recommended for very fast shooting).
If you want to shoot longer distances, print magazine_part2_with_scope_rail instead of magazine_part2. This part is equipped with an additional picatinny rail, enabling the installation of a short 4x32 ACOG type scope, but remember, this is not a sniper rifle, but a quick-fire weapon.