If I was going to buy a new engine I would go to HK and buy the ASP 46. Same as a magnum. Those engines are old OS castings that OS sold off years ago. Good motors and inexpensive. I use many different HK servos. priced from 1.99 to 10.99 and not had a single failure.

I know you use spektrum and that is your choice. I have a Turnigy 9x radio that I have been flying for three years now and fly electrics all the way to gas powered on it. with six and eight channel receivers. Cost less than $14.00 apiece. No problems no failures.

You could go to HK buy a ASP engine, 10 servos and with shipping and spend less than $150.00. I recently bought the new orange metal gear and standard servos at less than four bucks apiece and installed them in a Sig Sun Dancer Bipe. They perform flawlessly and I will not hesitate to buy more in the future. They are analog and I use them on a 4 cell nimh pack. Metal gear on control surfaces and a standard (nylon gear) on throttle.

If you do your homework HK has some wonderful products at a fraction of the cost of stuff in the states.

Good luck.