@krissy. A Google image search provides the following information.
Made by Gnosjö Konstsmide. Sweden; 1970's.
Image shows the same lamp with "G K " mark.
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Thank you @lexi. Yes, I came across that information as well. However, my lamp does not have any markings whatsoever, leaving me uncertain if it is the same model.
@krissy. It looks like the company still exists; you could contact them.
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