Alternatively go to the States and get yourself an FAA IR.
With the exchange rate as it is, it won't cost you much more than an IMC rating.
Then . . .
1) The CAA will 'give' you an IMC rating (for 70 quid)
2) You can exercise full IR priviliges in an 'N' reg aeroplane (there are plenty around for hire).
3) Because you will already have an ICAO IR, if you ultimately decide that you need a European IR, it will be considerably cheaper to 'upgrade' from that to a European one than to start from scratch.