Hi guys …just an update … i was able to source a secondhand replacement brake chamber unit of a guy that had an old 814 truck for breaking and he was quite local …during a trip to a local breakers yard with no luck the wee guy who works there told me he had one out at his place that had failed psv due to a lot of rust but the brakes had passed …£60.00 and fitted it myself … was actually quite straightforward just undid the old unit from the back of the hub … 2 half moon cover plates and 4 bolts and of it came …my van passed the psv test last week …happy days … thx everyone for your input …this forum is very handy 
Pic of my old van
