Your a bounty hunter. Selling weapons and ammo will be against the law that are willing to protect by becoming a bounty hunter.
If you are using the weapon it is deemed Legal. If a non BH is carrying the weapon its deemed illegal.
If you are going to sell those weapons there is a change you will be sent to jail and with that lose the 2 million Bounty hunter licence.
Rules wise i do not see a problem with you selling these weapons etc..
Be fully aware that if a police officer capture you doing it you will be sented to jail for dealing in illegal weapons and you will lose the licence.
" There are always dirty people around so why not a dirty Bounty Hunter "