For what it's worth, the 3/8" Alex Tech cable sleeving from Amazon fits these perfectly if you want to make them look prettier. It comes in black, red+black, and white and is $15 for 25 ft. It stays on securely on its own, but you can also use 3/4" 3:1 adhesive-lined heat shrink tubing at each end. I got the Eventronic brand from Amazon, a variety of sizes. The 3/4" slips over the connectors with a little maneuvering. A heat gun on low (750 °F) heat works well. The hotter setting on my heat gun (1000 °F) melted the Alex Tech sleeving. I would do a practice run, however, just to get the technique down. There is some glue from the shrink tubing that will appear around the edge as it shrinks to final size.
I just did this with a pair of these cables, and it came out looking very nice.
Good luck with the sale!
