Looks definitely vintage, and very nice. Could be a farm team. Here is a pic of a cubs A team in 1948 with similar jerseys, which could explain different tagging - But not a true Cubs jersey. In addition to the tagging being incorrect, the patch does not match a true Cubs patch. There is a subtle difference. I am not sure how to add a second pic to this post so I'll add a pic of the patch in another post.
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