It is such a simple fix, would be silly not to carry a spare. Less worried about breaking it internally as I am of contact with non moving objects.
Yep, which is exactly why I don't like the Warn Lock-outs. The only product that Yukon makes that I actually use and like is their hardcore hub kits for the 5.5" and up hub conversions and Ford stuff. More than a bit fiddly to get set up correctly but when you do, they are actually pretty neat. Very low profile, maybe stick out 1/2". Stainless steel so even if you do get into them, you may scratch them but you aren't going to break them on a rock, they default locked. That means you can remove the outer hub portion, tape over hole and drive out still locked up. (tape isn't required, just keeps the dirt out)
They have 3 notable downsides. They are very positive so they need some manipulation to unlock, usually turning the steering wheel back and forth to relieve the bind does it. Warn uses a spring that compresses to move the locking clutch when it lines up so they aren't locked until that happens. These are the opposite. The spring pushes them locked automatically and the hub lock pushes the clutch back against the spring.
They require knowledge of how stuff works to set up correctly. And the biggie is they are too much money now. Right at 400 for a pair of hub locks is ridiculous.