What strings for an old Gibson L50?

cgumtree

I've got an old Gibson L50 like the one pictured on Reverb, below. When I got it, it seemed to be set up with a heavy set of electric strings (maybe 12s), which can't be right.

I imagine it would have been a set of flatwound strings, but I don't have any experience with flatwounds. Can someone recommend a set that this guitar would have shipped with? Seems kinda fragile and I'm a little worried about putting it under too much tension.

https://reverb.com/uk/p/gibson-l-50-f-hole-1935-1971?gclid=EAIaIQobChMI4-n5xt_G6AIVFuDtCh3Xrg46EAQYASABEgKQtvD_BwE&hfid=19302389&merchant_id=118043958&utm_campaign=1726164661&utm_medium=cpc&utm_source=google