+1 for Paintman, their enamel paints are very good and have full Land Rover colour range. For base primer use Upol 8 Acid Etch, available in both tins and spray cans. I've used this for many years, it always gives an excellent finish and have never had a reaction with other primers/paints. If using an enamel you'll need to lay an enamel primer over an acid etch primer. Paintman have a clear paint process here
https://paintman.co.uk/the-simple-painting-guide/ , but I leave out the undercoat/filler/highbuild :.
- acid etch
- enamel primer
- top coat enamel
Spraying top coat is much less hassle than rollering and you'll get a better finish straight out of the gun.