I use Testors Dullcote for my matte finish, it protects really well, sprays on easy and doesn't darken your colors too much.
As for a gloss finish i just use the 'ardcoat from GW its a brush on finish but that works out for me because i never gloss coat 100% of a mini. That being said i use Testors Model Master Flat Clear Acryl as a brush on flat finish for the parts i dont want shiny, as Dullcote kills the shine of the glossy parts.
As far as i know all 3 should be available in the UK. Hope that helps you.
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