Silencer adaptor and thread question

[Megadeep]

I recently bought a silencer and due to miscommunicaiton the threads were wrong, it screws on the other way. The silencer has this little brass piece that you can unscrew out of it. I think I can buy a piece just like this but with the opposite threads (barrel threads). What I need is something that will screw on clockwise onto the barrel, then the silencer will need to screw on counter-clockwise onto it. (While shouldering gun) I'm a bit confused about this positive and negative threading naming convention. So what am i looking for? And where can I get it? Any help greatly appreciated.