For paint try Syphony Coatings:
https://www.symphonycoatings.co.uk/#:~:text=We%20are%20the%20UK's%20premier%20supplier%20of
They supply the trade. I have used them several times for paint for kitchen, bedroom cupboards and furniture. The paint they supply is used in the industry standard.
I have used acid catalyzed paint before for kitchen fronts etc, it's very hard wearing once it has fully cured. They have a water based paint which I am going to use for the kitchen I am currently making.
I use a high build primer and topcoat. Spray the hight build primer on the edges of the MDF and sand back with say 240 grit then spray the panel including the edge again sand back again then apply the top coat should work ok, does for me. Topcoat might be better with two or three coats for best results. The paint is touch dry pretty quickly but bear in mind it takes 30 days to fully cure once sprayed.