I'm still trying to identify them. They were made by Mahle.
The castings have inside them:
MAHLE 87P7+
138 55 (or 56 or W51)
I took some pictures to show them. Hopefully they show
up well. They have never been used and have 87.43
stamped on them, (not 87.50 as I said earlier.)
Thanks for the help!