I'll just add to my own info. My 990 is being crated up and shipped next week. Based on the info an being an expat I can bring it under RS plates.
There are a couple of motorcycle dealerships on the the La Marsa road in Tunis, just past the Carrefour by Sidi Dauod. A few sportbikes, 1200GSA, Africa Twin and it looked like the ability to get tires etc.
The bigger news is I found a KTM dealership in Tunis. Extreme Motosport. It is off the main Trans-African highway that runs N-S through the city. Not far from the Tunis-Carthage Airport. They have a new old stock 640 Adv on the floor and various ktm parts. They can also order in parts as need be.