That engine strikes me as a red head long stroke but that's just a "picture guess". It would make sense on a Loaded Dice III.

The old Webra web site is archived and linked here somewhere. A little digging should find it and you should be able to identify the specs on your beast.

Here are a couple of pictures I found of the older RE 61's. The one with the silver ring around the head is the long stroke while the blackhead is the short stroke.

David.