This is what I said above. Without a picture. I have installed these on two very short instruments and they work fine, with no rattles at the nut or anything. Plus they feel like bass strings, except for that naughty G string, which is unwound steel.
I even had a custom G string made that was wound (not straight steel), and it kept breaking. Eventually the manufacturer told me the tension was too high for a wound, G-string. So, to this day, I cringe whenever I have to play that high G string in a recording session. The tone is drastically different from the E, A, and D strings. I am working on using a separate pickup for that nasty G string with its own EQ. To make matters more complicated, I am using an ESP BB-5, which is short scale 5-string bass (yeah, that's right -- very uncommon). So, I also have a high C string that also sticks out like a sore thumb, sonically, to deal with.
Good luck. I think it's great you are trying to turn the bass into a melodic instrument. I front a band with a piccolo bass and the musicians seem to really like it. Check out music by Wyman Tisdale, Stanley Clarke, Julian Vaughn and the Braxton Brothers for upbeat music on the piccolo bass.
People have suggested guitar strings. The reason I don't like using guitar strings is I want a heavier string that allows me to pluck with my fingers, like a regular bass. I don't want a piccolo bass that just sounds like a guitar. It needs that kind of plunky sound to be piccolo, and I need to be able to really dig in when I play it without the rebellion you get from lighter strings.