My guess is that this is a Slatington team because it looks like the site of the old baseball field, the "S" on the uniforms, and the other photos in the group were all from Slatington.
This could be the American Legion Post 16 in Slatington basketball team. That is my guess since this postcard was in a lot with other Slatington photos. The American Legion was organized in Slatington in 1919.