I will let you know...
I have just found a supplier of Superpermalloy sheets, but the problem is that they should be cut through a special process to form the EI or C cores.
If anyone knows how to correctly cut these sheets please let us know in turn.
they said they are cheap since they could not provide ui lams i didnt get a quoting, but they send me their stock list - i can forward it to you if you´re interested.
i´m trying to find lams suited for a tube mic out transformer with dual bobbins - still not sure if the ui core is the only possibility, it seems very difficult to find.
this is great. i looked recently for the same type of materials. when i talked to oliver at tab funkenwerk, he said that he is now stamping his own UI30 lams because he was unable to get them, at least in the exact material he wants. i didn't have much luck either, but i didn't find marchandise.
magnetic metals here in the states has bought up some of the other lam manufacturers.
cinemag makes some dual bobbin designs, perhaps on DU124 lams? some version of the marinair 10468 is still being made by carnhill; that's a dual bobbin unit also. and of course everything lundahl makes is dual bobbin, some laminated cores, some wound.