Here is a list of the prohibited items which you cannot pay for using PayPal:
Firearms - Include all rifles, shotguns, and handguns, whether they are intended for use in sporting, as collectibles, or as curio and relic firearms. These items are prohibited regardless of their present working order.
Firearm parts - Include, but are not limited to, receivers and frames, silencers, kits designed to convert a firearm to automatic firing capability, high capacity magazines, multi-burst trigger activators, and camouflaging firearm containers.
Ammunition - Includes ammunition with propellant, such as gunpowder or blank ammunition. Ammunition is defined as ammunition or cartridge cases, primers, bullets, or propellant powder designed for any firearm.
Stun guns - For U.S. residents, PayPal allows transactions for stun guns only if the transaction is permitted by law in both the buyer's and seller's jurisdictions. U.S. sellers must ensure that each transaction is legal in both locations before completing the sale. Transactions for stun guns involving account holders outside the U.S. are prohibited.
OT Related Items - PayPal allows transactions for paintball guns, blank guns, and air-soft guns as permitted by law in the applicable jurisdiction. These items must display all markings required by law, must not be convertible to shoot a lethal projectile, and must not include blank ammunition.