http://www.thespicehouse.com/product/product_298.php

here  is a link to tomato powder. I wonder if the BIRs use this...

Next opportunity I shall ask whether they mean tomato powder is different to paprika.
But, yes you are right, tomato powder is out there!

I managed to copy the spice mix.
I only made a small amount.
This recipe makes about a tablespoon.

1 teaspoon paprika
3/4 teaspoon turmeric
1/4 teaspoon salt (yes, definitely salt!)
1/4 teaspoon chilli
1/4 teaspoon cummin
1/3 teaspoon coriander
1/3 teaspoon rajah mild madras curry powder

I am cutting  down on my spicing, these days.
I am sure they cover the flavour you are after

The curry gravy I made with this smells really good
I only used 1 desertspoon with four onions!

I agree about the salt it has made a huge difference since i`ve started using it, give loads of extra flavor ;D