Old MF12 Help!

Anyway the state of the machine: Open gas tank and it was clean! No rust. Decided to gas her up and see what happened. BTW this tractor seems to want some serious CCA's to turn over. My run of the mill garden tractor battery doesn't do the job. The engine started and ran well. There is a head gasket leak (no problem to fix).

Now for the bummer. Engaged the hydro tranny and got transmission fluid all over the floor. Pulled off RR tire to get a better look and can't really tell where the fluid is coming from but I'm afraid it's coming from the drive shaft of the hydro-stat. The tranny does try to engage and move the tractor in both directions. The very long belt that goes from the engine back to the hydro also needs replacing. Now I don't know what to do. I'm not the kind of guy who can drop a tranny and fix it. Heck even replacing the long belt back to the tranny looks intimidating. Anybody know if they sell parts for these anymore (like a new hydro)? Do people still repair old birds like these or would they just laugh at me at the repair shop? Any advice, encouragement, or estimates on what the damages might be to repair this would be greatly appreciated.