Wow, that's got to be a Shuttle Z at the very earliest. They used a short tailboom, high mount flybar and yours is set up for 4 channel operation as noted by the collective pitch and throttle links being on only one servo. This of course limits what you can do with this bird. You could get it flying but one crash and you won't be able to get rotor head parts for the high flybar config. At that point you are going to be converting to a ZX, ZXX or Plus style head where new parts are available. The OS .32 was a good balance of power, I'd imagine the .28 might be lacking a bit.

I'm sure there are better more complete Helis to be had, but much like bringing home a stray, sometimes life is more about the journey than the destination. Clean it up, you might be surprised what you find.

Tony