STEn MkII barrel with MAC threads ?

[Ready.Fire.Aim]

I saw a photo on a for sale board of a STEn Mk2 barrel with MAC threads.

What shop threads STEn barrels like this?

Note, this is not my SMG.

Thanks
RFA

 

[honda350xatc]

http://samachine.com/STEnMAC6.htm

 

[Ready.Fire.Aim]

The seller replied to email. He bought the barrel from Numrich years ago.

RFA