Shure Brothers made their name in phono cartridges.....
Shure is well represented at Music123 and Musician's Friend. Shure offers XLR cables, wireless mics and wireless instrument pickups, and so forth. I never heard about Shure having the people required to produce a line of loudspeakers nor have I noticed any Shure loudspeakers at Music123 and Musician's Friend.
You can try a Google search for Shure loudspeakers. If that yields nothing, then I would skip it because you may be looking at "White Van" speakers with phony Shure labels.
I have read enough accounts that suggest that Craigslist can be an iffy venue.
You do not mention price, budget, or objectives.
If you want excellent sound, go to Music123 or Musician's Friend and check out the active powered Mackie HR824Mk2 studio monitors at $600 each, delivered. Add an ART Studio MP Tube preamp at $30 for each Mackie if you can, and you are good to go by merely adding a DVD/CD player. The Mackies feature feedback control ["active powered"] to eliminate distortion, so they are very lucid yet powerful. They are (truely) flat down to 40 Hz and they start to run out of steam at 37Hz. This kind of rig should keep you happy for many years.