Hello, sorry to hear of your problems, give martin a ring at Sheffield subaru services, he may be able to source or know where there is a doner, 01142430099
Or there's grade a subaru spares on ebay they tend to deal with newer models and these guys may be worth a look too
http://www.subaru-spares.co.uk/
Your engine code will be on the vin plate attached to the top of the strut tower in the engine bay