Those old piano-key video recorders used to be everywhere in the 1980s. Thorn had loads of them on rental, and eventually they appeared in large numbers on the secondhand market as ex-rental machines.
They remained in use for many years, they were solidly built and fairly reliable but needed routine maintenance such as replacement of the belts and the cassette lamp. One reason why some people kept them going was allegedly they were not so susceptible to the effects of Macrovision copy protection which meant they were good for making copies of pre-recorded rented movies
I had a few of those over the years, including the "Deluxe" piano-key model with wired remote control and picture search, and a very rare multi-standard version JVC HR-3330TR (PAL, SECAM recording and NTSC 4.43 playback). I also remember Till's JVC / Akai front loading models, nicknamed the "Space Shuttle". When you open the front flap, it reveals a bewildering array of buttons and controls, a bit like the space shuttle would have.
Sadly I didn't keep any of these old VHS machines. I never imagined they would become valuable or collectible. When supermarkets started selling new VHS recorders for £40, secondhand machines became worthless - even repairs became pointless. Actually, when I think about it, I've got rid of lots of stuff like dual-standard TVs that would be worth money now, but at the time you couldn't give them away (I didn't know anyone else who collected such old junk). What's worse, some the stuff I did keep has remained worthless ...
Anyway, this should be a fun project. It's not too difficult to get these things working but as has been hinted, getting spare belts can be difficult now. Belt kits were once readily available, but not anymore since the cheap supermarket VCRs and then the disappearance of the VCR from mainstream use has pretty much killed off any demand for stockists of spare parts. Even "new old stock" rubber parts may be past their shelf life by now. I hope you can find the belt you need to restore it fully.