Relays are pretty much a common thing. Bosch makes one, so do several other folks, just don't get a Chinese crap one. You can get at any parts house. Take yours to the part store and they can match it.

2005 Model . Two Fast Eddy stickers , a bell and a clock . She's Lola . She tinkles and keeps time . http://s649.photobucket.com/albums/uu211/britbike05/