I bought two similar yellow plasatic ones at the Blackpool show two years ago ( not last October2008) from a gent and wife team.
Their stall was a big one with all things motors, shafts, props on a display board, glues knives etc, but I don't know their name.
They were on the opposite wall near the back archways, to metcalf mouldings as you come into the entrance to the hall, ( but sadly I can't remember the name of the vendors)
If anyone can understand my directions they may be able to give you the name of the trader.