Ian
go to somewhere like find-a-part.com, 247spares.co.uk, findapart.co.uk enter in your details and what you want, then tomorrow you will have 20 breakers phone you up, the first or 2nd, tell them you will get back to them, you will know what price they want for a 2nd engine, the 3rd and 4th and so on, tell you you have just been offered 1 for less than the last, they will soon come down in price
oh and use your credit card, that way if its knackered, you can claim it back from via the CC company