Hi TC,
Maybe you mean a curry powder made especially for chicken (rather than for red meat or fish....each with a different blend of spices)?
I know Baba's make, and label, curry powders in this way; though I don't know if they are available in the UK? I also know that many other suppliers do the same.
Any asian store, selling traditional indian foodstuffs, would sell similar curry powders and blends.
Otherwise, maybe you can consider making your own? Or simply use any decent curry powder instead?
Perhaps you can say why you need it TC? Then we might be able to help further?
Regards,