It'd be unlikely for your mortars to face direct attack (at least in this setup), so armor isn't really needed.
I'd go with regular, unarmored, Bv-206D if you really want tracked. Much cheaper too.
Question would be whether the terrain of the island requires tracked vehicles. If it's well-developed, somewhat densely populated, with a good road network, there shouldn't really be a need for them.
We have a overstrength regiment here, not a brigade. Of course, in several nations, it'd be called a brigade for political reasons.
In my opinion the air wing is overkill btw. Problem is that the size is already down to the point where it's simply a yes or no question - you could probably still bump it down to six fighters, but even then there really needs to be a good reason for this (rather costly) acquisition.
I can only think of generally two scenarios for such an acquisition:
1) would be that Bovania recently acquired a similar fighter capacity, and generally relies a lot on air warfare in doctrine; Sweden would also have to have denied Norland "fighter cover", leading to Norland acquiring its own capability in that regard.
2) would be an external pressure scheme (by Sweden!) in which Norland was required to buy these Gripens to "offset" some sort of international relationship toubles.
3) would be - simple - corruption.
In OTL, nations such as Lithuania, Latvia, Estonia, Luxembourg, all with comparable or larger armies to the two outlined for Norland or Bovania, don't operate any fighters at all.
If you really want/need a fighter squadron for Norland, i'd suggest something cheaper and "smaller" - say 4-5 light attack aircraft such as Hawk 51 or 100.
Would fit in better with the overall picture.