Sorry, I thought you were looking into upgrading your furnitures!... Just kidding
Here is the link
http://www.adirondackguitar.com/lefty/k ... sd_704.htmKen Smith Designs are probably the best Jazz Bass copies you can get for the price. $695. I tried the 704 (unfortunatly it was right-handed) and thought it sounded exactly like the Fender Marcus Miller. You get a bass with a real Ash or Alder body (as I said in another thread it IS the real Fender sound) with no need to upgrade anything. I agree with you on your estimate, all in all you are going to spend $600 for your SX and will still have an SX with a Maple body.
Good luck!