Silly. Anyone can build one for a .22 from common PVC pipe and fittings.
Seriously, I don't see the need for one on a .22 rifle.
The subsonic ammo I've used is darn quiet.
And the supersonic crack from high velocity ammo is louder than the bang.
Maybe an advantage on a pistol due to the short barrel, but on a rifle I don't think it would make much difference.