Gilliane, I will mail you directly re picking up the crude 'model'.
You will need to make sure it fits. I'm not sure how consistent the super seal 26 moulds were. Elsa is the later Parker version.
You will notice on the photo that there are short 'lugs' both fore and aft that slot down into the keel housing (where it is just marginally wider at the top). This is to stop the the fitting moving about.
The other critical measurement will be the width of the keel at the top. Hopefully that will be the same so it can squeeze between the blocks.
The blocks should be in the correct position fore and aft so long as you drill the new lower hole for the rope on the parallel line (with the keel edge) down the keel below the old upper hole.
You will notice that the reinforcement in my 'model' has a slot cut out of it (rather negating it's original purpose). That was for the 'pin' to hold the keel up through the standard hole ( I got that measurement wrong as the keel wouldn't lift any higher!)
It would be great if you could find a standard 'supplier' for this fitting ... it was a pity that my guy who made my ss one went out of business.
Chris.