You can try Amazon/Ebay or your local dealer. I just did mine. I used John Deere Top Sail White (Marine grade paint) and 4 coats of clearcoat. I have my doubts, but it looks fantastic right now! I posted a thread a few months about this http://forums.iboats.com/forum/boat...r/10087776-what-paint-is-best-for-an-outdrive. Good info in there with some more in depth methods.
I'm in the process of doing mine now. Stripped off all old antifoul paint (what a pain), treated bare aluminum with metalprep 79 and then alodine (both purchased through an aircraft supply), now priming and painting with Volvo rattlecans.