Is that for boat only or boat and motor? When buying new, you generally get what you pay for. What is the minimum and maximum length that you could use? What is the maximum weight? With used SIBs, some very good deals can be had, if you know what to look for.
One of the potentially best deals out their with used SIBs is if you can find an ex US navy zodiac FC 470 (semi tunnel hull, 1880 dtx hypalon) that hasn't been shredded to bits. They weight around 330 lbs. They sometimes go on Ebay for around 2000-3000 US.
As for new SIBs, I would focus in on either a Gemini Surf (tunnel hull available in hypalon or PVC), Arancias (inflatable v keel in hypalon) or a Ceasar Surfcat (tunnel hull in PVC). PVC is less expensive and tends to give a higher level of performance with the tunnel hull designs, hypalon is more durable.