100th Anniversary Purchase of Alaska First Day Cover

This cover is franked with the 1967 eight cent Alaska Purchase Air Mail commemorative stamp. Cachet Illustration shows a picture captioned “Secretary Seward and Baron Edouard de Stoeckl of Russia conferring over the Signing of the Treaty;” also an oval picture of Seward and a relief map of Alaska.  Cover reads, “100th Anniversary Purchase of Alaska 1867-1967.” Postmarked SITKA, AK, MAR 30 1967. It’s in a protective plastic sleeve.