Is this the pump you have?



If it is, then these motors will work:

2 speed:
http://www.a1poolparts.com/-strse-16...eed/Detail.bok

1 speed:
http://www.a1poolparts.com/-strse-87...are/Detail.bok

I'm not necessarily recommending A1, though I have purchased from them myself -- I'm just using their listings as an example.

Meanwhile, there's some long-time marketing gaming with pool motor HP ratings (uprate vs. full rate), so that a 3/4 HP 2 speed probably is equivalent to your 1HP single speed.

Verify that that's the right pump, and I'll take it to the next step.