Ooh - takes me back seeing the old girl - this used to be mine, and Burritobass's before that.
I'm certainly no expert with acoustic guitars but this one has a particularly sweet tone; I always liked the very funky bridge and pickguard design, and the pre-war style logo.
I think the output jack connects to a concealed electromagnetic pickup and is original to the guitar, but I could be wrong - I never used it, but was told the amplified tone is lovely.
A rare and vintage Gibson for not much dosh, with the added bonus of dealing with a Basschat legend.......