Rather than the milk, I buy the solid blocks of 100% coconut (there are a few different brands, think the one I have now is Island Sun). Then, for the easy option, just throw a chunk of it in your curry along with some water. Or you can also reconstitute it into coconut milk by dissolving in hot water, the texture is bitty but if you then put it throught a fine sieve that makes a nice smooth coconut milk/cream.
Noticed the other week that Planet Organic now have coconut aminos.
I think we're lucky in the UK that many lightly processed foods (especially canned ones) are compliant.