TorqueTalk:
You are correct that you can easily get an SEIR(H) in Sweden and I'm sure the Norwegian authority is more than happy to put it on a Norwegian issued JAR licence, cos of mutual recognition and all that.
The point I was trying to make is that the UK CAA don't really give a crap about JAR (unless it suits them). Even though ratings and licences are mutually recognised (and by definition REQUIRED to be accepted by other authorities), you will never get a SEIR(H) rating put on to your UK issued JAR licence, period.
So what happens when you pay that (only slightly-smaller) fortune for your Bristows SEIR on the JetRanger? You get a piece of paper. Basically your test pass certificate. You are then supposed to submit that when you apply for your ME rating and MEIR(H), only then will the UK CAA put anything remotely IR-related on a Helicopter licence.
If you're self-funding the IR, like Helimutt said, pay the extra and do it all in a twin. After paying all that cash for the IR I'd certainly want something more than a thin piece of A5 tissue paper to show for it!