Probably stamped in China. Could be a hang up in material suppliers, issue with the press, they all then need to get EDP coated, and a few weeks of transport to get to US shores.
..stuff happens. They have a significant amount of part variations and probably make long runs of each part to get the economy of scale behind those parts and not constantly changing tools.
Have you tried YearOne or another big outfit to see if they have those parts in inventory?