Yes, the release pin is there but I haven't tried any other tension assemblies - yet. I do have a spare beehive spring (seems a little large) and nut that seem to fit over the stud. I think that I need three disks. I think it might be similar to the unnumbered 66's. However, since it has a decent stitch the way I have it threaded, I will probably just leave it for the time being. I don't "DO" eBay, let alone German eBay.
Janey - Neat people never make the exciting discoveries I do.