Is this a South Korean used US uniform?

[Bavarian]

Hello
I found this intresting shirt for small money
It seem to be a US Type in cause of the stiching and the colour
The ink stamp seem south Korean but I am have no idea
There is no label inside
In the Korean war the South korean army used US M1 and Uniforms
I am thankful for all ideas
BR
Bavarian

[Anderson]

Certainly appears to be South Korean issue from the stamp mark.

[gel65]

The shirt itself is South Korea as well, the South Korean's had their own military uniform that they produced themselves. They were just heavily influenced by the American Military. Since it's not Marine stamped I'm guessing its Army 1950s/60s period