Actually they have two locations, the yard shown in the link, and the Yardstore. a simple Google search using each name will show each location.

Work took me back to Wichita today so I visited the Yard this time instead of the Yardstore.  I thought I found cheap grooved combination square type rules at the Yardstore,  but I was wrong! At the yard, link shown above I found tons of rules, grooved and not with lengths uo to 24. All factory seconds, most of them $1 each, 18" & 24" grooved were $2 each!  I ended up buying 11 rules there and spent $13. Two of the 11 were 12" grooved 4r, and 2 were 18" I think 6r. I  don't know if they sell online like HJE though.f

1940's-1960's is my guess.

pick out the issue..............besides its being a found on road dead ford

sometimes there's a label on one of the drawers, or possibly the side panels somewhere, that could hold clues.

picked these up from the Channellock web store