First things first
Years ago I once owned a Yellowstone truck camper, not that it means much, however I do know it was very heavy for its size. I suspect the travel trailer is built the same way.
I suggest taking it to a truck scales and obtain the actual weight before making a decision.
Yellowstone RV's have been out of business for many years, so the few specialty parts will be difficult to locate. The upside is, IMO they are a well-built product. The appliances have nothing to do with Yellowstone, they are purchased and installed.
With a trailer this age, water damage is a huge issue. If you don't know what to look for, consider hiring an independent RV technician to inspect it before you let loose of your money.
This interactive towing calculator
will be of immeasurable help with properly and safely matching your tow vehicle to a trailer.