I have a 52 gas engine from HK (1st mistake) that the shaft that holds the prop on was drilled off-centered. I cannot get any place with HK. What would that part be called. On the prop end it has a 10mm x 1.5 socket head bolt holding the prop on. The other end is bolted to the crankcase by 3 bolts. The unit itself is about 2 inches long. I don't know what it is called and don't know where I might buy one. Like I said, after many emails to HK it looks like I am going to end up with a paper weight that looks like a gas engine. Thanks in advance for any help.