You're new alright.

What are the odds this has already been discussed, numerous times even, and there were a way to review previous discussions on the topic or even search for them?

The only locking diff is the factory one so far. Should have bought the Off-Road model instead. Now you're stuck with your short-sightedness.
It does appear that ARB is developing a locker for the M226 (D44 type) rear though.
If you have the C200 rear axle, there's a chance an ARB could work in it, but I haven't heard of anyone doing so.
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