... Finding the right shades of rainbow

I need to paint the large prop I'm making in the three primary and three secondary colours. Normally I would be reaching for my acrylic paint or spray cans, but for this item, emulsion paint is probably the best bet, so I had an interesting hour at homebase (Home Depot) trying to figure our he best colours on the Dulux match cards.

Having seen all the colours together, it did make me wonder who on earth would paint their walls in one of these vibrant shades, but there again my bathroom is red.