you have a picture of what they look like? i was looking through my bins of 55-59 parts i was given (mainly gmc stuff) and found a ash tray.... may be the right kind?
------------------
www.xframeimpala.com
68 4x4 short fleetside deluxe cab 327 air
56 big window short stepside 235 dual 1 brls
64ImpalaSS 327
70 C10 LWB fleetside custom/10 350/TH350