Those CO2 cartridges are standard, cookie-cutter items. They haven't changed in decades.
I can’t confirm your question… but if it were me, I’d take one received from Northern Brewer to a Wal-Mart. Head back to the sporting goods, where they sell CO2 cartridges. If the 12 gram cartridges are the same size-
Out of curiosity, do you use the CO2 cartridges for Corney kegs or is there another homebrew use?