Yes
Or you could also use the 75AX 2 stroke. 2 Strokes aren't necessarily a big no-no. And for the OS, you can get pipes etc for them too (Important as you move up the grades and are forced to comply with the noise regulations).

I started with a Swallow and a Saito 1.25 that I had laying spare. It was overpowered with that engine.

There are a bunch of threads on the Swallow here. Do a search - there are a few tips on making them better and a bunch of suggestions for the engine.