Not sure, it's a group based out of Canada and they only recently started stocking the TA-66, and my guess is they are are still in the process of getting them in to ship out. On the plus side I don't have to pay duty! I'm pretty used to either having to pay a ton to ship from out of country or...

I guess one benefit of having to wait a month and a half for my TA-66 to ship is getting to see the results of other people experimenting with it

My understanding was that there are equivalent tubes that exist but these are two different form-factors, and if you want to use a 12AX7 tube you need an adapter, which for me in Canada seem to go for 20 bucks or so a piece But I could totally be mistaken, I don't know a ton about tube amps yet