Heyo! Head of AMA's Cosplay department here.
The specific staff to inquire would be Security and you can find their contact info on the convention website. They do all the final checks and peace-bonding at the convention for all props.
If you're thinking about competition and bringing it on stage, I personally have no issue with most weapon props as long as you follow simple guidelines:
1) NO LIVE STEEL OR EDGED BLADES!
2) Be careful how you carry your prop. No breaking of stage or equipment, or you'll pay for it. And it is expensive...
3) Anything vaguely gun-like that is frowned upon by Security can be used on stage and only on stage. Tuck it away after that. Sorry, save picture time for later and away from said Security staff or they'll get mad at you. The state of Virginia has an EXTREMELY strict shadow gun law that allows any police officer to shoot first, then ask questions. Hence, most prop guns aren't usually allowed at any Virginia cons...
Always check with Security if you aren't sure.
Remember, peace-bonding is usually a tag or bright zip-tie that allows any other staffer to know that you have taken your item to Security and it has been approved for the weekend. Do not swing your prop around or mock-battle with someone else during the convention. You'll get Security on you rather quickly and trust me, you don't want to waste time arguing with staff when you can be smart with your prop and enjoy the con instead.
I hope this helps!