Mint never used envelope / cover from the Pacific Stage & Express Company - printed in the early to mid 1860's. See below for more info on this historic stage coach line!
Illustrated stage coach print with PAID. No address.
These are getting harder to find. I was able to buy this a few years ago from postal history dealer Steve Taylor.
Pacific Stage & Express Co. was a private regional mail and passenger stagecoach carrier that operated in the American West during the early 1860s (active roughly between 1861 and 1866).
It ran stage lines and delivered express mail between major locations in California and Nevada, including San Francisco, Sacramento, and Virginia City.
The company is well-known today among postal historians and collectors for its rare printed "franks" (pre-paid or authorized stamps/markings on envelopes showing a stagecoach illustration) used on U.S. stamped envelopes. [1, 2]