I use a Kimberley synthetic endurance saddle made by Downunder saddles. I'm well pleased with it - construction is good, it weighs next to nothing and is comfortable for horse and me. I fully plan to get a second one but need to decide between another endurance or their synthetic stock model. As an fyi, the endurance model uses a regular english style girth while the stock model requires a special australian style design because of the overgirth.
For either one of these saddles, the price would be well within your range. If you go to the Downunder site, they have a clearance section and you can frequently get good deals there.
A couple of comments about the synthetic style: I have not had mine long enough to see how many years you can actually get out of them before they wear out. I have still not come to terms with how easy it is to care for - I can't seem to get used to the idea of not having to oil it at any time.