I'll try and dig out the number for you - will also try and get the shop details. My stepdad was big into windsurfing at the time hence going with a Tushingham...
Great to see another one still out there. I've just spent the last few months restoring one too. Its been in the family since it was bought from new at a windsurf shop on the south coast. Nearly all original (rear tyre, saddle and the forks needed replacing). Pics below.