Hi moragwilkie.
You could try a call to this number: 01495 792700
Website is:
http://www.caravanbreakers.net/
Try putting 'Caravan Breakers' into Google and see what comes up, as this could provide you with a few more caravan breakers.
Alternatively you could also put 'SMEV' into Google and see if you can get a contact in the UK as the sink/cooker is made by them.
Our sinktop smashed on a trip back from Ireland and I ended up getting a replacement on a trip to the Czech Republic!
It was while on holiday but it only cost me £35 and not the £65 that Hobby wanted.
Good luck!