They are definitely not boots, I've had them open. Not an eeprom in sight. They were all toshiba chips on SNK boards I think.
They were however in shitty condition.. Dirty, scratched up, etc.. The serial numbers on my KoF98 look like they were burned / melted off! Although old used MVS carts are rarely in great condition. I definitely expected Waku Waku 7 to be a boot at that price, but it's a 100% real US/English cart with a low serial number and is in great condition compared to the other carts.
I paid by credit card, but you can pay them by bank transfer (I don't know how you do that) or western union. For western union you take your money down to a western union agent (usually travel agents and some post offices) and give them the money (plus a bit extra). Then the person you're sending too picks up the money from their local western union agent. It can be expensive though as I think they charge a percentage of what you're sending.