Defo a boot - aside from the remarks already made about the case, late official AES games never used those sealing stickers iirc.
In fact, those large translucent sealing stickers went out of circulation around the time SNK moved from soft cases to snap-locks. They then used a small round neo-geo logo sticker (in colour) for a short period, before abandoning them altogether (circa 1997) (and I think these were only used in Japan as well).
However, NCI and other onion wearing outlets of questionable repute, started using them in their bootleg releases. If you ever see an NCI boot that's still "new", it will be sealed with one of these soft case style seals.
So, see a late or high value AES game, US or Japanese, with that old style sealing sticker anywhere on the snaplock case - be very, very, wary of what you're buying.