Note that there can be bimetallic corrosion IF water leaks are allowed down thru around the U-bolts. Some owners of many kinds of boats believe that the original sealant will last forever. Not true. At all. Not even a little bit.
About 30 years is a good point to pull and re-bed all (deck) penetrations. Ericson's will probably go that long, and lesser craft will be lucky to make it to 20 years.
While waiting for your new parts from Gauhauer, route out the coring around the holes, over drill, epoxy, and re-drill. We did that on the same fittings on our '88 boat, last year. Our original SS fittings were OK, and no deck leaks, yet.
And, as Stu and Alan are urging, log in at the Ericson Owners' site.
www. ericsonyachts.org.