My recommendation:
Classic & Modern Engine Services Ltd
18 Great Hollands Square
Bracknell RG12 8UX
England
+44 1344 488853
I always was very satisfied with their services. They did work for me and many others I know (in fact, it was those others, who recommended them to me) on classic car engines, dragster engines, and stockcar F1 engines. I know that they did work for Icelandic Formula Offroad and Rally teams and they do contract work for BMW UK Ltd. which is also located in Bracknell.
They have the latest machining equipment from America, the newest stuff imaginable.
The shop looks like a clusterfuck, but don't let that put you off. I've seen them do work for McLaren and Judd.
Can't you locate a used engine in Iceland? From a crashed one for example?
If you'd like to go down that route, i can search for one in England, too.