Hector, yes you can add a pistol brace, not a stock. A stock would make it an SBR and be subject to registration and $200 tax stamp. Have a great day!

Yes you can put a brace on it.
There are several models that come with a brace already installed.
Out of stock right now but hit the notify me when available button to receive an email when they come back in stock.
budsgunshop.com/search.php?q=Stribog+pistol+brace&type=

Yes, you can easily add a pistol brace to this. Hope this helps.

Hector, yes Sir you can put a Brace (Not Shoulder Stock unless registered as an NFA firearm and $200 Tax Stamp) : https://hbindustries.net/store/shop/stribog-bt-type-stock-brace-adapter-sbt/