Hi res decals for a custom autoharp: The Minstrel of the Dawn

This is an expensive custom made autoharp by a master luthier. The project will take some months for him to complete, and I want to be ready with the art work that will make the thing truly my own. I'll have exact dimensions, file type, and resolution requirements shortly. We're looking at three or perhaps four illustrations, each not more than 6 inches long by four inches high, and none of them with regular edges. No squares. These are to be made into high quality decals, which are placed on the soundboard and under the finish. While guitars are usually adorned with marquetry, autoharp makers more often use decals. The theme is "Minstrel of the Dawn", and the figures are 1. A medieval troubadour in repose, holding a lute 2. A night sky of stylized stars, planets, and the moon, perhaps in crescent with a face. 3. A ring-shaped illustration, again a night sky theme, or perhaps a theme that suggests some kind of cycle or repeated process, or even a beautiful geometric pattern, to go around the sound hole. 4. Possibly something else that fits in with that scene; perhaps a bower, or flower bed in a pastoral setting, perhaps some other medieval or pastoral idea, or which blends the ideas of music, the musician, and magic or the night. These decals will be applied to high quality Sitka spruce, a very light-colored wood with a tight grain, and then covered with several light coats of yellowish but very translucent varnish. Colors in the illustrations should be muted, not bright, but should account for this coating. Metallic colors such as silver, gold, bronze are desirable, particularly in the stars and moons illustration. Depictions should be classic, not modern. Figures should be more naive than realistic. Facial features should be beautiful without being overly detailed. The whole feel is of Western Europe in the Middle Ages, and the theme is courtly love and ballad. The final product is a high resolution digital file that the luthier can make into a high quality decal. If there are any physical work products, like sketches, I'd like to have those too.