That's a bummer Roger...
I've got one in pieces. Its definitely possible to rebuild it, but its going to lose some length (not travel) - about 15mm I think. I figured that you could extend the fork and redrill the hole to regain the length.
The only thing that's stopping me is that I can't cut the new snap-ring groove inside the shock body.
The valving is whacky old-old-old-school, so I wouldn't even guess at how to change it.
So... I wonder if the answer is to send my shock to Sean - bet he'll say: "Oh, that's all? No worries".