I got this out of an old weed whacker. It was locked up and I soaked it in penatrating oil and got it apart and cleaned it up. The piston and cylinder are scored, the rear bearing for the crank is rough, and I can turn it over by hand pretty easy. The compression is low for sure. Is this worth saving? I have all the other parts. Also what is a fair price for a new converted Ryobi, and what is a fair price for a used converted Ryobi?