I just got in my new 90/22 High Tower Armory bullpup stock kit for the Ruger 10/22, so far it’s been pretty impressive. I was shopping around for sling options for the bullpup stock when I stumbled upon this single/two point hybrid sling from Urban-ERT Tactical Slings. Their Urban-Sentry slings were designed to be used specifically with the new HTA 90/22 stocks and are available for both left and right handed shooters various colors. They go for $66.95 over at UrbanERTSlings.com.
Just a note, the picture above is of an actual P90, but the sling for the 90/22 will look very similar.