Barrel thread/silencer attachment [several guns + makes]

[Grif 2200]

Hello

How can I find the barrel thread measurement in order to attach silencers to a few of my guns.
It's purely aesthetic for photoshoots and filming, so if it's going to fit, but not fire, that's still good too.

I'm not particularly handy, or knowledgeable when it comes to anything to do with editing/changing an airsoft gun, so any help would be appreciated.

I've got a TM 5-7, WE Glock 19 and an SRC MP5, which comes with a flash hider.
Any particularly easy ways to check the measurements for these? Is it universal? Any help would be appreciated. Thank you