Update.  I bought a standard bucket tooth from the Cat dealer.  I had to grind a bit of the mount away to get the tooth to fit but it goes on great and works fine.

I've finally started using the machine.  I spread out a few piles of dirt at the house, and today I drove it the last five miles over to the Tod Engine Heritage Park.  She really flies in sixth gear.   As long as the swing motor holds up (I've heard these can be problems) I think I'll have a good working machine.