[Milsurplus] Source for Leather Washers ?

[Mike Durff]

John & others: 
You might try the hardware distributor linked below. They are an "old line" hardware distributor. They may not sell to you directly, but could possibly provide you with a retailer near you. My better half went to work for them in 1966 as a keypunch operator. They were then located at the end of the street where I grew up in Memphis, TN. They are now the world's largest independent hardware distributor. The chains like Ace, True Value, Home Depot & Lowes only carry items they think a homeowner or small contractor may buy. Our local hardware store was supplied by Orgill Brothers until they switched to an "Ace" franchise several years ago. The difference in stock was like comparing daylight to dark.
 I would compare them to someplace like McMaster-Carr,  with the emphasis being on hardware.

https://www.orgill.com/index.aspx?QType=100162