Wow, i get those for £3.50.
Expensive it is, just bear in mind like BGHunter mentioned in his post about peoples interpretation.
Look at the gallery and make sure the colours you've chosen compliment each other like the original colours do.
You may have to change some of the colours you already have.
Also look into alien paint that montana and belton do, maybe misting the transparent alien paint over a certain green will get a close enough colour.
also the colour changes when you dull coat it. you have alot of thing's to account for. you have your work cut out.