DarkRP ammunition problems with FA:S 2.0

I have a DarkRP server and I need to know how to only allow ammo to be bought and sold by a custom job I’ve made (called Ammo Dealer). The firearms my server uses are FA:S 2.0. Somebody help, please.
Thanks, Matches

Bump

If you know how to code you get the Ammo Dealer job files and the ammo put them in there that should fix it only if you know how to code.