Not 100% sure but couldn't you do a side-by-side comparison with a few dimension checks?
Failing that, I'd stick 'em in and see if you can gap them to spec and static time them with a light bulb.
A word of warning though.
If these aftermarket items are not TEC or ND brand, they could be difficult to set.
I've had to order some very expensive originals from David Silver 'cos the aftermarket ones were poor quality.
Good luck!