The USPC records, at least for crest and seals, run from 1911 to 1938.

I don't know if USPC made chips before 1911 but they did make chips up to 1947. First large guess on my part is that most of the USPC crest and seals not in the records are from the 1938-1947 period.

The really old crest and seals (the ones with water stains and lifting inlays) are pre 1911. Inlays for the pre 1911 chips were made Whitehead and Hoag out of Newark, NJ. The inlays were paper with a celluloid covering. The company specialized in pinbacks.

Below is a W&H pinback to the left of a chip whose inlay was made from the exact same material and same size as the pinback. Celluloid and paper worked for pinbacks as the graphic was he'd in place on the reverse with a metal ring. Such an inlay combination didn't work so well with chips as there was nothing in the chip construction to prevent the inlay from lifting. In 1911 USPC abandoned the celluloid/paper inlay in favor of the celluloid/celluloid inlay.

Question is: who made the pre 1911 chips. Did W&H supply USPC with the inlays or did W&H make the chip. W&H seemed to make whatever they thought the consumer wanted.

By the way, why do you think your die cuts are older than the usual ones. Look fairly usual to me.