If your friend is skirmishing he has a defence. You don't need anything like a 'UKARA' to own a RIF, you don't need any kind of permit to respray one if you are skirmishing.
If he has sprayed it black he doesn't need to respray it to any other colour.
There is a some bad info being passed around in this thread.
A site shouldn't be asking you any questions about where or how you got your RIF. It's nothing to do with them.
If he has a defence he can spray his two tone any colour he wants.
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