Assuming you live in Swindon there is a shop on Manchester Road called Grace Electrical who repair that sort of thing there or can come out.
I'd always been a big fan of Grace, until my last visit, when they sold me the wrong thermostat for my cooker, when I put the bugger in it quite literally blew up, and tripped out the circuit.
I'd taken the old one down, and was told the replacement they had although not looking quite the same would do the job.
I trust people like them so a bit disappointed...