if you want a new one here it is Britcar (UK) Ltd > YWY000080 ALARM RECEIVER 433MHZ UK-EURO DIS11(G) or google out the part number and u'll find lots of trustfull suppliers
Can you just fit a new receiver or do you have to have it remapped with ECU.?? What i mean is, can you just fit new for old and plug it in and it works..