Yes, so I'm not really complaining, especially $18 in the scheme of things is insignificant. It's just the markup on this particular item that shocked me.
And to reiterate, the new pin I bought for my car, part number 944 105 170 04, does look like an upgrade over the one that came in my car. My original one did not have the grooves to accept the two o-rings, nor of course the rings themselves. If the o-rings help contain the grease between the pin and the pivot, the new design should be an improvement over the original, especially if, like me, you track the car periodically. As I said, my pin was bone dry when I took the pivot out. The belts were replaced about five years ago, so I guess I would have expected some of the grease to survive, assuming the mechanic who did the belt job last properly greased the pin. My car's a '92, so I'm not sure when Porsche changed the design, but I'm glad I went ahead and replaced mine. Oh, and the pin is only $50.40 from Paragon, not $56 like I had thought. I've temporarily misplaced the receipt for the o-rings, so I don't have the part number handy, but when (if?) I find it, I'll post it, in case it helps somebody who's preparing to do this job if they want to shop around for a better price. I was in a hurry, and Paragon didn't have the part in their system.