Bill,
I have a couple of the late ScottAtwaters ( 10hp) and an Elgin 12 (14hp) both are painted like the one you showed ! As Dave said it’s all up to you as to how authentic you want to be ! Personally I enjoy running them more than worrying about whether they are vintage perfect !
Mummbles, If the picture of the ScottAtwater 30 is yours, beautiful job ! I had a 33hp years ago but gave it away, sad as I would like to find another one !