Hi wizard69,
I have had that same thing happen to me many times here in Calgary, some dealers are just too lazy to look through a few catalogs and make some calls. What were you looking to spend? I just ordered a seatcover for my '97 CR250, it was an OK price, the first shop I called simply told me they didn't have any, they didn't offer to order one or anything, so I called somewhere else.
I wouldn't buy one for a different bike, it might look like it will fit and then after getting it mostly on you will notice its a tiny bit too small. Then you can't take it back.
My advice is shop around, you should be able to get a seatcover for about $75 Canadian. Another option is get an uplosterer to recover your seat, that may be much cheaper, and you could pick any color you want.