Frames to store signed posters

I got a poster signed at Moonbyul's LA stop yesterday I want to frame it, wanted to see what y'all have done for similar items to protect them. After doing my own research online I see a lot of people talk about using a frame with matting to keep the signature from touching the glass, as well as if protection glass. I've never been a fan of matting in frames but I do want to protect it, so I'm hoping to find one less than an inch thick if anyone happens to know of anything like that? Where have y'all purchased frames for signed items before? Thanks!