> I would like to find a good stiff piece of horsehide. Needs to be at
> least 3 in by 12 in

You're probably interested in horse butt, which is very fine and tight
grained and excellent for strops.

TFWW sells in 15" x 3":http://toolsforworkingwood.com/store/item/MS-
HORSEST

or you can buy by the pound from Siegel
Leather:https://www.siegelofca.com/view_cat_product.asp?id=80
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