HO scale Neon signs of a more Mature nature? - Model Railroader Magazine

I had this subtle little business by the tracks in my industrial district, "Alternative Lifestyles Pub, Entrance in Rear."

Seriously, have you thought of perusing some, ahem, adult web sites for banners and such that they use for advertising their sites? Most sites of any kind use stylized images and so on to advertise their wares, so you may be able to find something along those lines on an adult site that you could print on clear styrene and light from behind if you cut out strategic areas to look like neon. If what you find is too explicit, you could tame it down using a graphics editor like Photoshop. You could also search for businesses like adult clubs and see if they have images of their neon signs.

Another idea is to find someone who is an art student or has some art training, since human figure drawing is usually taught as part of art curriculum. Someone with that background can develop artwork you could use, maybe for a mask that you could overlay on clear material and paint the non-neon places a dark color for contrast when the light is shining through.