This really depends.
NA originall manufactured their 10.4 barrels with both gas port sizes, depending on customer request. Depending on when you purchased it, it bay be one or the other.
Original 10.4 barrels meant for non-vented GBs were ported at 1.4mm and the barrels made for vented GBs were ported at 1.6mm.
To truly understand which gas block you need, requires a proper measurement of your NA barrels gas port.
If you have a 1.4mm gas port, your options are:
1: to get a non-vented GB (which i would heavily recommend you not run suppressed due to excessive bolt speeds, damage to your dissconnector, excessive carrier tilt, and damage to the rear of the ejection port caused by brass impact.
2: get a vented GB and experiment with different strength springs and buffer weights until you find the combinantion that will reliable lock the bolt back on the last round.
3: have the barrel gas port opened up to 1.6mm and get a vented 10.4 gas block.
If you keep the 1.4mm port, choose to use a vented GB, and experiment with different spring and buffer strengths/weights, ensure the last round bolt hold openpeoperly works when dirty and dry or you'll be dancing on the line of full function reliability.
In my early days of learning gas port/gas block combos, i would find a combination that seemed to work when the gun was clean that would then later fail to lock back after the gun got dirty and dry.
If you have a 1.6mm port, you really should run a vented GB and stock spring and buffer combination as that's how the gun was set up from the factory.
If you choose the experimentation route, i'd recommend using the different strength springs from sprinco, and getting one each of the different buffer weights (carbine through H3) so you're nit constantly driving out the buffer roll pin to change between steel and tungsten weight combos.
As of this writing i have a 1.4mm ported barrel that i have a vented GB on and the full array of springs and buffers to test, i just haven't gotten to the range yet.