The number on all draw knives I have seen, refers to the length of the cutting edge, as to the YAL I don't know.
On your second knife I believe the name is probably the makers mark, as owners marks are not normally stamped that deeply. As far as who he might be, the following is all I could find.
The EAIA Directory of American Tool Makers shows only an Oliver Sawyer working in Bolton, MA from 1804-1836 as a maker of draw knives and other edge tools. He is the only maker of edge tools listed, although there is an S. Sawyer who made coach makers tools and planes, but dates of when he worked aren't listed.
The first initial looks to me like either a K or an R not an E.
I want to change my mind. An E or possibly an F? Although still no help.
Mike