Great project Rolland. Well thought out magazine as well. If it shoots as well as you hope it will, you can always retrofit a CZ straight feed mag into the well.
Straight feed mags are so much easier to work with.

Take a look at Gun parts corp under Heym parts. They bought out all sorts of parts from older bolt, combo, and DR models. Plenty of sites, bands, etc for less money then is worth putting into them to make yourself
https://www.gunpartscorp.com/search#query=heym

Cheers,

Tom