$30000/$30=1000 replacement '360 controllers.
Now you just need space for all of them.
I guarantee that for something as fundamental as the main periscope control, _everything_ is going to have replacement parts. That's why $30k is so expensive, it's not $30k, it's $60k or $90k or $120k. Now they have the kind of problem that's fun to have: for half or quarter of the cost of replacing that proprietary controller, they can have so many '360 controllers they won't be able to store all of them on board.