The problem is I have seen many shades of Kewanee Green so even if you found some there's a good chance it won't match.
TOB
Or, you might get the Model A paint chip book sold by most suppliers and take that chip to be color-matched.
That would be the standard to which all Kewanee Green cars are painted. But alas time and the local matcher originally may conspire together to make your car a different Kewanee Green.The problem is I have seen many shades of Kewanee Green so even if you found some there's a good chance it won't match.