Machiel Kalf has doggedly tried to organise a display of recognised +4 Supersports built by the factory. So I'm afraid all those beautiful "lookalikes" will not be invited into Machiel's enclosure. [-X
Leigh Sebba sent me a list of what he knows still exists in the UK - it still seems to stand at around 7'ish.

To-date, I am unsure as to how many Supersports will be there but knowing Machiel, it is likely to be the largest collection on SS's ever seen in one place.
Are you taking your's Simon?
As for other rare ones - Leigh can update on +4+ (unofficial +4+ resistrar!!)...........and, are all the SLR's turning up I wonder? I've heard on the vine that the convertible EB bodies car will be there.....that will get you searching through your Mog books.
So who's going? Perhaps us 4 cylinder chaps can meet for a beer or such like?