If you're going to use the horn for jazz, get a .500 or .508 bore. Something along the lines of a King 3B or Bach 16. There's also a new model by Yamaha (697Z I think) that's been getting a lot of positive reviews. The Getzen jazz models are nice too. They're basically as good as Edwards, but without the modular options, and they're only half the price of the Edwards.

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If you want to get more advice from people who know more about the small bore horns than I do, sign up at the Online Trombone Journal Forum. Lots of knowledgeable people over there. I'm mainly a large bore tenor and bass trombone guy.

alright tahnks for all the help

wwbw.com
great prices on everything for what you get.
if you know what kind of horn you want, ebay might be your best bet.