[systems_glitch]

Excellent recommendations, I'll also add if you're not in a hurry Edcor makes excellent transformers (plate, filament, combo, output, interstage). Everything's custom made when you order it though.

Hammond Manufacturing makes a lot of applicable transformers for the mid-to-lower range of hifi and they're largely stock items.

See if you have local hamfests. Tons of tube stuff there.

Remember, it doesn't need to be an audio tube to pass audio! My most-used amplifier is built around a pair of 6T9 TV Compactron tubes (basically the IC of the tube world, multiple elements in a space saving package). The circuit came out of an old GE vacuum tube manual. As long as you don't tell the electrons (or audiophiles), they'll never know!

[JKCalhoun]

Edcor are made in the U.S., Hammond ... in Canada? Both excellent transformers - and probably the most expensive part of the build (the tubes I use go for much less than the iron).

[systems_glitch]

Yeah, that was always the hard/expensive part, building tube stuff as a kid! Most of the junk radios and TVs I scrapped for parts were AC/DC sets with no transformer.