I got my wiper blades at Napa, they are correct fit and look and work just fine. 6-700 seems about right for the windshield. Used is an option, but a 50 year old windshield isn't any good, the new ones are MUCH safer. The vinyl that is used in the middle of the glass is different than the ones used in the 60's. The ones from the 60's tend to cut your neck very bad if your head impacts the glass in a crash (your head pokes through, and as you are flung back to your seat that's when you get cut and die) the newer ones do not do this.As far as keeping scratches from the wipers in the first place it's kind of hard to do. The metal arms bend as they get used, wind changes the way they sit on the glass, the blades wear down....and scratches will happen. The only 100% way I know is to use something like Rain-X and never turn on the wipers. The glass can't get scratched if the wipers don't move. I've used Rain-X in the past and been very happy with it.if you really want to use your wipers check out the wiper switches from 59-64 Chrysler full size boats. Most of them have variable speed wiper switches. You may be able to install one of those switches in place of your two speed switch. The cars are almost the same underneath their skins. (Same windshields, wipers, wiper motors...etc) I've not seen a '64 with a two speed switch, I've only seen a single speed switch or the variable speed switch. But anything is possible with mopars. I would also think that nearly any aftermarket wiper delay (JC Whitney might sell them, or Napa) should work with our cars. Nothing really special about the wipers that I can think of.--Eric SturgisTacoma, WA1962 Chrysler Newport 2 door HT