Hello Mike,
I can't help with ID for the yacht but I can point you to the VMYG [Vintage model Yacht Group] with a website at www.vmyg.org.uk they might be able to help.
Russel Potts is one of the contacts to ask, he seems to be a font of knowledge on vintage yachts.
As to the keel, yes, I've seen old yachts assembled like this. It enabled the yacht to be broken down to hull, mast rolled in sails, and the keel plus lead in a bag, then the owner could hop a bus and go to the water for a sail. Also, many of the older yachts were also sailed on salt water in the sea. I'm currently restoring such a yacht which was raced in 1911 in Strangford Lough, NI.
Good luck with your restoration, Kimosubby.