[sreilly]

It's a copy cat plane, made in a new city in China - USA, OYVAY Province, China. They'll do anything to cash in on a potential market.

Looks like a Stanley #5.

I was thinking along those lines but Stanley usually had their name etched on the blade instead of just saying USA. I found a Stanley plane guide that was excellent for dating plane. Try this link as a fast way:
https://www.hyperkitten.com/tools/stanley_bench_plane/dating_flowchart.php