Sorry - no, I don't know anywhere else. There will be a complete list of approved schools on the CAA website, though, you could start by looking there.
Do you mind if I ask why you want to go abroad, though? Are you actually planning on using the IMC rating when you return to the UK? Of all of the licenses and ratings, the IMC is the one which I would definitely not recommend doing abroad.
The thing which the rating prepares you for is, basically, flying IFR in IMC outside controlled airspace. But the vast majority of the world doesn't understand the concept of IFR outside of controlled airspace, so I would expect you will return to the UK without any real understanding of how to use your new rating. If the reason for doing the rating is just to get some experience to help with the IR, then that's fine... but if you have access to an appropriately equipped aircraft and intend actually flying it in IMC, then get some training which will teach you how to do that - and that means train in the UK.
Just my opinion, of course.
FFF
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