Not worthless for sure. As Joe said, Classic Center requires a core. Possible they would buy old ones? Might check. With the values of the 3.5 W111 cars going sky high, restorers will want that piece of the puzzle.
I had mine rebuilt by Boge/ZF and is working well to this day. Shipping was a bit of a pain as was transferring the money into the native currency. In all, I saved a good amount. But for the US folks, now is a great time as the exchange rate with the Euro is a whole lot lower than when I did it. Today it is almost 1 to 1.
I can try to dig up email contacts for ZF/Boge if you want. That was 5 or more years ago, so who knows if the info is fresh.