The 1953 standard cab interior color was "Sheen Gray (Metallic) Poly" (on all but Suburban). I do not know about interior colors for 1951 and 1952.

PPG/Ditzler 31104
DUPONT 202-81407

"Each color order receives a spray-out panel and is CERTIFIED by our LAB to be correct to standard." I wonder how they certify 50 year old colors?