This thread is long, so please forgive me if I'm repeating too much.
So you can get H motors from 161 Newtons all the way up to 320 Newtons.
There's a common misstatement that I usually manage to bite my tongue and keep quiet about, but not when someone is looking for basic educating. H motors range from 161 to 320 Newton-
seconds (Ns) not Newtons (N).
Ns is the unit of impulse and of momentum. N is the unit of force, average thrust in the case of rocket motor designations.
As to the motor codes, just remember that they are essentially the same for all the motors. Look for the letters that come after the average thrust and and after the delay number, and ignore them. The propellants that are represented by those letters do have different characteristics, those characteristics are 1) burn rate, which is already reflected in the average thrust number, and 2) cosmetic. Cesaroni places a number before the letter code for impulse; that's the (more or less) exact impulse, more precise than just the letter, but you'll see that anyway in the motor description.
As others have said, use simulation tools and ThrustCurve.org; keep it simple; and don't rush.
Finally, don't overthink it. If you follow the advice above, L1 certification really isn't hard.