Thanks, but it's no cheaper than anodising, and I've got the kit to spraypaint as good as cerakote.
Cerakote is extremely sensitive to shortcuts in the prep.
For Cerakote:
The part must be soaked in CLEAN acetone for at least 30 minutes, not wiped.
The part must be shot blasted with CLEAN grit of the right size, and all grit blasted off with a CLEAN airline.
The part must be heat soaked at 120C to 148C depending on whether it is E or H series.
The part must be examined for any oils after heat soak prior to coating.
The coating must be mixed precisely AND the filter used
The coating must be baked for the specified period at much higher temperatures than other paints.
I have lots of photos of Cerakote flaking off things, from simple mistakes such as a clean acetone dip after blasting.
On cold anodising, many companies do it in the UK but the colour choice is grey or black, AND the black then runs if you soak it in water. If you want pics, PM me. You may as well use standard anodising and give it a coat of PU varnish.
Flexible surface technology in Livingston are good, though slow. They do a proto batch for £100 fixed cost and have a range of colours. I get small runs of coatings done frequently, and use 6061-T6 mostly.
Or, make it from titanium where anodising is really easy and you get nice pretty colours.
Or as someone has suggested, and what I would do, is make it out of steel and blue it. Ali rails never seem to stand up as well as a proper steel rail.