Light green paint means up to about 1980 so it might be newer than your tractor. Quality of those is at least as good as the red ones. The gear case is likely cast iron, instead of aluminum with a sheet-metal shield at the bottom, for example. It may include wheels which were discontinued later. Tillers are simple, there's no technological advance as they moved to the next generation. Worn or broken tines are what you should examine.
The tractor half of the top link is what keeps the tiller from running into your tires when you lift it. You might need to find one. Or if the seller used it without problems then he may have lengthened its driveshaft and moved its lower mounts forward to solve this. (A slip clutch added in your driveline will lengthen it too).
Good luck with this!