These are 3 1/2" speakers, they are tied to the door speakers on the radio, and most any aftermarket speaker will do. You would have to change the connectors in the harness, though, since in my Daytona the harness has "V"-shaped faston connectors for + and -.
I have made adapters for my 1987 Shelby CSX. Go to an auto parts store and buy some not spade lug but the blade type male, female crimp on connectors, and a short piece of wire.
The male crimp on connector should push into the wiring harness connector.
Crutchfield is a good resource, and they include an adapter harness for the dash connectors, it plugs in and then connects to the replacement speaker. Good luck on finding used ones, a lot of Chrysler vehicles used them, vans, the Sebring convertibles (probably sedans too). I have yet to find a good pair in a junkyard.
Audiovox 110T-1085 replacement speakers are the best if you can find them. They are the sps series and should or used to be available at dealerships for around 7 to 8 bucks each. They hold 20 watts easy if the bass is not cranked way up. You can tell when they distort so just fade to the back a little. Your existing connectors can be used if you push down on the release pins and pull them out of the plastic. They are quarter inch terminals. JVC makes a good three and a half speaker albeit their terminals are different. Just observe the polarity and either will sound great.