Totally co-incidentally (really) I was going to put a Helyett from a similar period for sale on CR - any way here goes - and I think I am quite a bit cheaper than the Ebay one but mine does need restoring...
HELYETT ROAD FRAME c1963 Seat Tube (ctc): 58cm Top Tube (ctc): 59cm Rear dropout width: 120mm Wheel size: 700C Seatpost size: 26.6mm This one I think must be a little later than the Ebay one for it has Simplex vertical drops ands a full Nervex Pro lugs, BB AND fork crown. I rather suspect the Ebay one is earlier than the seller thought. My one is is very sound but it probably needs repainting; there are the remains of the seat tube decal there and the head badge is the same as the Ebay one... It is also inter4estingly the same colour. A slightly more reasonable price at 145 GBP
Pictures at:
http://i141.photobucket.com/
Hilary Stone, Bristol, British Isles