That engine will be a great match for that plane. As far as the gear goes, you can use the stock gear and just cut a block of lite balsa that is about an inch thick and the same size as the stock gear block, coat it with a thin coat of thinned epoxy and epoxy them together. Seen a few of these done this way and it looked good as the block was rounded and covered.

If you really want a good looking gear that's about an inch taller, there are several places that sell C/F gear. TNT is one of them and I also think they make an aluminum gear that is taller for the SSE.

I used C/F gear myself

That is a great kit to build. I did 2 of them, one got an OS46AX and the other got electrocuted and both flew very very well. Just build it straight and you'll have no worries. If you can, try not to use the nylon control rods that come with it. Heat and humidity will cause your trims to change. I replaced mine with 2-56 steel rod without any issues.

Other than the taller C/F main gear and replacing the control rods, both were built bone stock with no problems