Yes, finding tubes isn’t a problem for the most part. The ones that are hard to find are the ones that found their way into highly desirable equipment and had short production runs, or for very early (pre WWII) radios. For a while 7591s that tested weak were fetching $100 each on eBay until the eastern bloc tube factories noticed and started producing a decent copy. The types used in radios and TVs are long out of production but there were so many millions of them made that it’s not a problem even finding new old stock cheaply for most types.
I have a variant of this console, it goes by the name Schenkendorf. Too bad I did not see this thread earlier. The bar area is supposed to light up when you open it.
Any ways, I have a membership to radiomuseum.org and I took a look at the schematics. If you were to wire this correctly you’d have AC side that goes to the voltage selection taps (110, 127, 155, 220, 240) on the transformer be the “hot” wire and the other the neutral. I’d also suggest grounding the chassis as a precaution.
Also, from within the record player area, on the top, you should see four screws. If you unscrew them you can take the chassis out. But, you will have to mind the knobs and what not. I have not taken my chassis out so I can not fill in the details. If you like the radio it might be worth it to remove the chassis and send it off someplace to have it recapped and have new tubes put in.
You can also remove that record player to put in a newer one in. I ditched the one that came in mine as it had a non-replaceable steel needle and it wasn’t worth the time.
Well, works of German engineering, some of them. 
The sound from the turntable was actually really lovely - warm and very rich. Sometime today my slip mat is supposed to come from Amazon and then I’ll get to play around with it!
Glad to hear you managed to get it working in the end! 
Furthermore, were you able to fix the AM and Shortwave on that turntable too?