Peckmore often worked for Harry Lindquist’s ‘Associated Etchers’. For him, he etched a version of Houdon’s Bust of Washington, and of Stuart’s portrait of the same man. Both were meant to accompany the US stamps with similar portraits, and were advertised as such in the mid 1930s.
Peckmore also etched a number of designs matching the 1937 National Parks issue, and an etched version of the Penny Black in 1940. Finally, there’s a specimen stamp engraved by Peckmore, which is based on the US 10c stamp from 1847, although unfortunately not printed in recess. It is thought that Peckmore used these when trying to get a stamp contract with Liberia.
Peckmore apparently also engraved stamps for Haiti, the Dominican Republic and the Republic of Guinea, but more specific detail is lacking.
Harry Peckmore passed away in 1975.
You will find Harry L. Peckmore's database HERE.