The size is correct for an 'ENTERPRISE' from the 1950's which I used to sail out of Broadstairs in Kent. The sail code is a capital 'E' if you have the mail sail?
'Marlin' ?? did you mean 'MERLIN' as in 'Merlin Rocket'. sailed those too, very fast and totally the wrong shape. Merlin was 4.4 metres with a 2.2metre beam. They have a tall thin black isosoles triangle on the main /forums/images/graemlins/wink.gif
I think it will be something unusual like a wineglass (or simalar) - equally it could always be a modified boat (lots of this age have been - i.e. take an old lark hull, and add a rear tank and change the mast step for something easier to use to lower the mast singlehanded - seen this quite a lot - not convinced it is a lark hull though....)