The high bidder just bought a 1973 GMC motorhome on ebay two months ago. So if you want it make him an offer, I'll bet it is for sale. The other serious (i.e. non-zero feedback) bidder also looks like a dealer.
A bargain, I do agree. The sellers didn't help the sale along by disavowing all knowledge of the coach and insisting the sale was without recourse. A virtual invitation to a dealer (or two) to lowball them.
Fuel prices may have played a part, but a minor one, I think.