What type of paint should I use to paint Mattel belt strap?

I have never painted anything whether it is a figure or belt. I want to paint the strap of one of my Mattel Winged Eagle belts, but have no idea where to begin as far as what type of paint (brand/style/etc) I need and where I can buy it and what type/size brush I would need. I'm looking for something that will not cost too much, but also not look cheap. My figures are for display only. I've seen Larry Axe Hennig's work of a painted Winged Eagle belt which is exactly what I want to do

If anyone could give me any help here, it would be greatly appreciated. Thanks so much!