Edz, Thanks for your brief history of the German photo industry. However, I think the question was where to get Tetenal minlab chemicals. I looked at page 21 of Fotoimpex's catalogue and lo and behold: (a brief translation) we have the complete assortment of Tetenal products....if you like to order large amounts etc..please ask for an offer.
Whether they still export to the US is also matter of sending them an e-mail.

Greetings

Hans