DB,
Oh, your pictures of the drive shaft bring back memories. On my boat I cleaned up all those parts with a wire brush (on metal parts), soft brush (near/on the outdrive shaft seal...careful with that seal), and good old WD40. As stated I chose to replace my u-joints, but to be honest they didn't look too bad internally as I did have marine grease in them. (in other words the u-joint pin bearings were still in good shape even after the water got in there)
Remember, search the internet for your parts as you will find better prices on one site to the next.
Hey, if you can let me/us know that Phoenix welder guy's name or business that would be great also.
Best of luck
Offrddrver