Haha yes brother the inside is impressive, in its own special way
The outside is in fantastic shape so the decks are probably fine, and just need new belts and maybe a little bit of grease. Maybe clean and demagnetize the heads, and refinish the pinch roller. The forward/reverse switch inside the upper deck will probably need a spritz of Deoxit.
I'll assume they can figure out the sizes on their own, but we have known good sizes. In fact one member here recently found a better size for the lower deck that gives stronger rewind power.
If they want more than $200 I'd probably pass on that. I know others here have found local techs to service their boxes, perhaps one of them might be able to say whether or not that's too much for a full rebelt.
Woops I forgot you're in Canada, so that's about $160 in the US. That may not be too terrible if they get it all working!