No offense but for $13 you can order the basic bullet guide from CSS..
15 round mags are going to tough.. might want to use factory 10 rounders.
Must be in NJ.. the 15 rounders gave you away.. (lived in NJ for 35 years)..
You can possibly take SGM AK/Saiga mags they come in 10,15,20,30 I think..
or use blocks..
http://www.magazineblocks.com/magento/universal-ak-10-30-block.html
then mig/tig weld the bottom shut to be in compliance for non-removable base..
**I am not a lawyer, this is not legal advice.. YMMV..