Well, you COULD make your own. Get either white or clear rounded cables. I would probably go with the white. Get yourself some red UV reactive paint. Walmart has some acrylic for about 44 cents a bottle. Makes sure to shake it up really well. Take your brush and paint the cable. If you get a decent brush (also available in the same section in Walmart), the brush lines won't be too bad. The paint is kinda thin, so you'll probably need at least two or three coats. It says to allow an hour between coats, but I've found that it's thin enough that if you wait 15-20 minutes, it gets pretty dry. The first coat will act as a primer, you won't be able to get it on very thick. After you have your first coat on there, add a second or evena third thicker coat.
Voila, red UV reactive cable.