James,
You are going to want one servo with decent torque, for the rudder. Possibly two, as it looks like the elevator is on a bell crank. The ailerons you can get away with 60-70 ounces of torque. I run all Airtronics digitals.
The digital aileron servo's I run are tiny. They are 94761 At 6.0 volts they have 66 ounces of torque. They weigh .80 ounces. They cost 59.99 each
I run 94758 servo's for elevator and rudder. They have 115 ounces of torque at 6.0 volts.
All the servo's I run are fast servo's. They cost 99.99 each.
They are all good servo's. You can buy them here http://www.warrickcustomhobbies.com/...ex.php?cat=226 at those prices.

I recommend a pcm receiver.
As for battery, there is nothing wrong with running a 5 cell nicad pack in your plane. You will obviously want a good regulator though like the Jaccio perfect switch with regulator that central hobbies sells. I run lithiums though. Not required..

As for the Y.S. Good luck my friend!!!! Never had the best of luck with them.
Muffler.... A few options are the Hatori 698 which I ran I think. And also one of the carbon ones. There are many to chose from. You might want to see what sweetpea ran as he already has the exit hole but in the bottom of the fuse and pipes are different lengths..

I think I've covered your q's.
Don't think your q's are silly. Ask anything. We'll try to help..
If you can't get the Eclipse there are some good alternative's out there in the 90-110 range that may be a little easier on the pocket book.
One way or another we'll get ya pointed the right way...
Chris