Diamond wheel locks for Elddis caravans?

Jules26

We recently bought a 2012 Elddis and the recommended wheel locks are the Winterhoff Diamond wheel locks. They seem to be hard to come by!  

Does anyone know a supplier of these in the Yorkshire area?  We have contacted Wandahome Knottingly and Catterick Caravans near Richmond. Both said they had to be specially ordered in! Catterick quoted a price of £700 plus two hours labour cost to fit (so
£1400 for the twin axle caravan then!!) Any suggestions would be welcomed. Thanks