bout the only thing I could find for a quick inline tap is 22-24 gauge (which if you squash it enough, I have seen the blades of these things poke out the other side of the plastic)
expensive enough (geez)
leave you a few options, wirewrap to larger wire then solder and inline splice it (really once you get the hang of it its like 5 seconds to wrap, 30 seconds to solder 40 "pins" ... though it might take a week to get the hang of it heh) , or strip a good 5 or 6 inches and fold it up so it doubles its size each fold to mimic a 24 + gauge , or squash the crap out of it with some channel locks (works well enough in my past) and hope you dont cut the 30 gauge
if you dig around enough 3M makes some telephone grade taps, but they also top out at 24 gauge (and I havent had much luck finding them)