Well.....whenever you get to a point of being beyond "mental masturbating" (imagine the vocal sounds of Robert Plant during the "space-out" period [2:10 - 2:20] of "Whole Lotta Love" !!!), 1) send me PDF files of all of your component datasheets, 2) Let me know of the size and shape of the enclosure you would like to have and I can easily enough whip something up for you!!! Unless, of course.....you are able to find some BUD or HAMMOND enclosure that fits your needs. Then you can "hack and whack" as is necessary to make everything fit and go together. YAY!!!
I was looking at the ANTEK toroidal transformers myself for a special "Power Distribution" project I was thinking about. These transformers were in the neighborhood of 1,800VA and 2,500VA and the ANTEK's became too pricey for me.
[Let's not overthink this with all sorts of "I can make this better" ideas] -- OK!!!.....I personally am not "thinking" or "overthinking" anything whatsoever!!! I just saw this thread about some guy needing to put together an AMPEX 350 power-supply and I simply offered him my expertise of performing 3D mechanical designs in order to help him out. I do, however, find it a bit unusual that the OP (SoulSystem) has not responded back to any of the comments left here in response to their original posting. That then makes me think that their wanting a "New/Old" AMPEX 350 power-supply isn't really - THAT - important to them after all. So.....because of that, I am guessing that this thread is actually a "dead issue" from here on out!!!
[I did find a Triad candidate for the B+ filter chokes] -- Well.....as I have stated previously, once you "git yer shit tahgezzer", send it all to me along with with however you envision the enclosure to be and I can whip you up something pretty nifty!!! And, as I have also mentioned previously, I (or, you) can e-mail my CAD-file to one of several specialized "prototype & low-volume" sheet-metal shops that I am aware of in order to have your enclosure fabricated and shipped to your front-door.
Whenever you're interested in tackling this project of yours, just let me know, OK??? Maybe send me a PM would be best.
By the way.....I have browsed through your website and I have seen what you have accomplished "long, long ago" and I am very highly impressed with all of your end results!!! I was actually thinking that it was too bad that you and I didn't know one another "way back then" and teamed up to be a "design team" together!!! THAT would have been a FUN THING to do together!!!