blowers are virtually universal, and specific only by the voltage that runs them. There will be indoor and outdoor installations, but if you are installing under a spa frame, you can use either. Also, you will encounter different horsepower ratings. Try to match the one you got as closely as possible. You may have to do a little engineering if you can't find an EXACT match, but it's fairly simple to do. If you need a copy of your owner's manual, one can be found here in PDF format:
http://sundancespas.com/Communications/ ... 700Man.pdf