It’s very hard to say, 12.3 is very strike fighter heavy, best comparisons are the Mirage 2000, which as far as I can tell is only that low as a holdover from before the Magic 2 had IRCCM, and the F-5A(G) even with 4 AIM-9L/I should be worse than that. The other comparison is the GR.7 Harrier, which has the same loadout and no radar, but a worse FM, with better RWR and more CMs, as well as all it’s A2G weapons which does increase the BR even for air.
At 12.7 I’d say it’s entirely outclassed except for maybe the F-20A, however even that has a lot of things going for it over the F-5A(G) and like I said, I think that should be 12.3 anyways
The Norwegians will have upgraded it themselves to accept the Penguin, if they didn’t use Mavericks then there is no reason for them to add that capability.
From what I can see Maverick capability came with the F-5E, or at least that is the earliest version I can see that used them
AIM-9M would play nicely into it receiving Python 4 as well once that is added.
I also wonder what launch rails are used under the wings and if they would be capable of mounting other LAU-7 capable missiles like the Python 4 or AIM-9s, though that might be a stret h considering it was only used in Thai service to mount Python 3s.
I think you’re forgetting just how much stronger the engine is on the F-20, as well as how big a difference having a functioning radar and AIM-7Fs makes