Exactly.
16" barrel is not an SBR unless OAL is less than 26".
So, either the OP is looking for an SBR or not an SBR.
In one case, it is not an SBR and a single stamp. In the other, it *is* an SBR and is a double stamp.
Tacsol took a slightly different path for 10/22 barrels
As have a couple other companies.
A friend of mine told me he yesterday that he was about to order one of the TacSol SB-X barrels.
I offered only two bits of commentary/advice:
1. If the base cap gets stuck on the barrel threads, it could be a real pain to remove. (TacSol's own Ascent 22 is one of the worst designs for that.)
2. Make sure your can fits.
He sent me a message a couple hours later. "Good thing I measured. My suppressor won't even fit inside the muzzle cage."