Inside the housing at the carrier bearing there is a drive shaft torque tube seal, which is the part that is leaking. Other parts needed will be the carrier bearing rubber bushing and the universal joint housing and bell gasket set. You might also need a carrier bearing and universal joints. Of these parts, the only one that I know for certain that has to be purchased from the specialty vendors is the carrier bearing rubber bushing, and possibly the torque tube seal. The bell gasket set is still made by fel-pro. The carrier bearing should be available from a local parts store, but I cannot recall for certain. The universal joints that are exposed are available through a local parts store, but the enclosed u-joint (at the tranny) is not available, as far as I know.
The driveshaft is not that difficult to rework. It can be done without a press, but some mechanical aptitude is needed. If I were taking it to a shop, I would at least get the seal and the cushion before I went in. You aren't too far from Chevy Duty, they should have the parts in stock. Also Jim Carter and LMC are in the area.
If you need a good mechanic, I do know of one in Olathe, he rebuilds 67-72's on the side. Back channel me if you would like a contact.
