There were some 10" Radio Shack woofers in there when you got them, you told me. I encourage you to post the model/cat. no. on the back and condition as in a lot of cases it can be looked up and you can get specs or at least Realistic/Nova/Optimus speakers they were used in and search from there. For many years Radio Shack actually sold some very good replacement speakers that you wouldn't be the least bit ashamed of.
10" woofers make for some very good sounding speakers in a nice size too...KLH Model Six, RS Optimus 1 and 2 have been some of my favorites.
I have seen search hits that mention these JBLs in quads (sets of four) and that makes a nice arrangement too, one that spreads the stereo power out efficiently through the room with better matching of sound quality throughout.
So yes, post pictures for all of us. It would be very nice, as well as the price you want and try and figure out shipping weight and dimensions...the methods some shippers us to determine prices have changed quite a bit in the last two years.