briggs and stratton model number

Hey, I have an old briggs and stratton engine I got from a friend. Its quite old, and I was wondering how much HP it has. I was looking at the site http://www.briggsandstratton.com/display/router.asp?DocID=65324 and I can find out certain things but not the hp. I have the haynes book for small engine repairs but it only covers 5.5 -20hp engines. The number on the engine is 80302 943058 5903210 . If anyone has the other book (book#10340) or they can help it would be much apreciated. Thanks. - Andrew