Any chance you could put up a photo? The green might be a somewhat common candy colour or close enough you might be able to fix it? It would be a lot of work though. Typically, a coloured clear over raw goes something like this:
1. clear primer
2. candy intercoat
3. intercoat clear sealer
4. high gloss finish
So it's pretty tough to replicate for a touch-up, but depending on what it looks like, you might be able to get it down to as simple as a two-step paint application for a touch up.