The JAA IR skills test must be taken in a JAA member state. There are various schools offering training combinations of the first 30 hours of the IR in the US, with the last twenty hours completed at a European based training partner. However if you complete JAA IR training in the US you will often pay a mark up compared to the equivalent FAA IR training. I recommend you either complete a full JAA IR course in a JAA state; or complete an FAA IR in the US and then convert to the JAA rating. Anyway it can be beneficial to have both FAA and JAA ratings as this creates scope for working on N registered aircraft based in Europe. I knew of one school in the US where the JAA approved multi IR training was 295 dollars an hour, whereas the FAA multi IR was only charged at 180 dollars an hour.