I think from what you have said Hayleys advice of Eggbert or Catanache seems logical, you'll find these on the for sale page, I hope they are on budget they are certainly available now and sailable for the nationals. I am Brightlingsea man and you'd be welcome to come over one weekend, however my boat is of the new radical side and I'm not sure that would be good for your back !
Be great to meet you though, I remember some of the old Dabchicks crowd from the late 70's and early 80's