I use visa GC's all the time online and off and never had a store turn them down. Not exactly a seed bank though. I'm under the impression Visa is Visa. Email their support, I'm curious what they'll say as well.
Yea that's how I ordered my beans. Make sure it doesn't say "Only accepted in the US" or something like that on it. There are only a few that don't around here but you can find them.
I use to order from dr. C ( but i think he doesnt ship anymore) , And i was thinking about buying from gypsy but then i was kinda paranoid cus i heard sometimes they dont come through along time ago I was thinking because they are located in Amsterdam and customs see thats its from Amsterdam so they might look into it more. ( or on their packages just blank and it doesnt say it came from Netherlands. Amsterdam. Any one know any Good seed banks in the UK that ships to the US??? or some good seed banks that has alot of seed vendors like Dr. C I dont want to buy from high grade cus its 50 bucks,(i wanted to order alot from nirvana