Almost surely manufacturerd for Western Auto by Duro Metal Products in the late 1930's, early 1940's. The Duro and Indestro models were marked on both sides of the handle, the Western Auto models were unmarked. What little I can see of the knurling on the sockets looks like the plain ribbed knurling Duro used on its own sockets until mid 40's when it went cross-hatched. Those holders, with the L-handle holding the sockets in place, were a Duro/Indestro thing. Nickel plated. Ratchet is hollow, made from two pieces of pressed steel. The other end of the screwdriver bit is the drive plug!
I've never seen one so complete in such good shape.
Really nice find.