A muffler that short with no baffle must be loud AF.
After almost hitting a deer one morning a few years ago I decided I needed something a bit louder than the stock Honda muffler, but I didn't want an exhaust as loud as the Two Brothers full exhaust I had on my Ninja 250R.
I settled on a Delkevic DL-10 slip-on. It has a 14" can and no baffle, but it's exactly the "noise level" I was looking for. They make everything from stubbies to 18" mufflers with baffles that are probably as quiet as stock.
Lots of options, good quality and reasonably priced compared to a Yoshi or Akrapovic. Delkevic
I have a stainless Delkevic slip-on on one of my cycles, and it has a removable baffle to control the sound. I modified the baffle a bit to get the sound I wanted - deep, but not loud. It was too loud without the baffle out, but too quiet with it in, before I added a hole (probably about 3/8", but it's been a while) in the end of the baffle.
TrueFaith posted above with a Delkevic link as I was composing my post.
I've had mine for almost 15 years, and it's still good. I'd recommend stainless over carbon in the long run.