Astralwerks has put out a ton of classic electronic albums. Metal Blade was great back in the 80's and 90's, but they've really gone to **** these days.
If you're including youtube channels, Thebestdream I had is an excellent channel that posts a ton of obscure 60's and 70's bands. Discovered many great heavy psych/metal bands from there:
https://www.youtube.com/channel/UCQh...5BemCTp5nv8CwA