Hi everyone!

I've got a problem with my Gibson LPJ's G string, it sound really dull when working on the 1st and 2nd frets, for example an A power chord using A, D and G strings. It sounds dull and almost out of tune even though it's not.. I'm thinking it might be the string pocket that's a bit narrow?

I know I could easily expand it, but I figured I might just aswell buy a backup nut since my band's got a gig soon, and I don't want to screw my guitar up this close to it.

Any thoughts?
A nut takes some time and skill to install, you can't just buy a "backup" one and pop it in before a gig. On top of that, there's no need to get a new nut just because it's slotted improperly.

I'd take it to a tech, I wouldn't be surprised if it just needs a little shaping on the nut, or some minor fret/truss rod adjustment. This doesn't necessarily sound like a nut issue, you should probably have someone diagnose it before you start swapping out parts unnecessarily.