I have the originals off of my GTX sitting in a box in similar condition, I have noticed prices in the 3-400 dollar range also...seems there are a lot out there for sale so I also don't know if they are actually moving at that price, there were a few pair at the last swap meet I was at tagged at 400...they didn't sell...
1968 Plymouth GTX 440 4 Speed Dana
1973 Small block Duster under construction
1974 Dodge P/U Long Bed Stepside 318 Auto
1975 Jeep CJ5
2016 Dodge Ram Hemi 1500