Being in Canada I can't help with the price, but can give you a few tips on the Mercury.
First and most important get it check out by a certified Mercury mechanic before you even think about buying it. The Merc can be a great engine when properly serviced and maintained, but when things go wrong it can be tough to trouble shoot, and expensive to take to the dealer. The Mercury engines are outboard power heads attached to a jet pump, so if you ever have to replace it it will be on the pricey side.
When you do look at the boat have a good look in both ends of the jet pump and make sure the impeller and the surface around it are in near perfect shape. If they are beat up at all they will need to be replaced. Have the gear case, and stator fluids checked and look for any signs of moisture or metal in the oil. Get a compression check done and if possible get them to find out the hours on the engine.
When working good the Mercurys are great engines. I have had no problems with the Optimax in my Utopia, and have nothing but good things to say about the power, and fuel usage.
One last thing, don't bother with Sea-Doo dealers for service, because most of them are not qualified or equipped to work on the Mercurys, you need to find someone who is.
Aaron:cheers: