It is most definitely worth restoring. A lovely item. Works just as well as any number of more prestigious units.
Covers are available on eBay, just check the dimensions. Belts ditto, and if by Head, you mean the cartridge, then again no problem. Probably the best value for money these days is a new Audio Technica, but if you want to be historically accurate, you could get a Shure cartridge body on-line and buy a replacement stylus, or just buy a replacement stylus for the cartridge already fitted, assuming it works. If by Head you mean the headshell, and yours does look somewhat bent, they are available again on eBay.
S.