I purchased a larger 2" dimater fore-shaft on eBay a while back. Turns out that was too big for my original or spare rear driveshaft so it's been collecting dust. What's more funny is that my parts donor P1800 has exactly the same length foreshaft, but the rear shaft is the one that's too short. The 1800 has a big flange, and the 122 has a small flange, so I was faced with some flange incompatabilities. I was lucky anough to find both a short 1.75" front shaft and a J-type small diamter output flange in Canada after posting a "wanted" classified here (Thanks Pierre!).

The responses I got were great, but several needed the measurements, which I did not have.

I also made contact with Chris Horn from washington who sold me some other needed bits and (I think) has a D-type '68 that he's parting out after an accident. Since I have a J-type OD, I needed a different flange to put my setup togther so he couln't help me there. However, he might have just what you need.

I can send you his e-mail address later this evening if you like