Never ever have i seen a WMR headset cheaper than $400 AUD, let alone $250.
No idea how many are left, but I own a WMR headset and it is very comparable to the Vive.
Note: This is a refurbished model, and a 4 year warranty is available for $3.50 USD
Good luck!
The item I got is used but not refurbished.
Package: no original box, 1 headset with bag + 2 controller with bag + 1 cable + 2 batteries(not 4)
Condition: The foam seems being heavily used and broken at the edge, there's a broken sticker I have to remove with alcohol because it's melted and very sticky, and there are debris and hairs that I have to clean. And there are smudges on the lens that I need to wipe. But the outer surface of the headset and controllers looks like new.
Testing: works well for the first use, will update if there's any problem
Overall, you get a used one, you may have to do the cleaning, or maybe replace the foam to let it look like new, and there's a few months warranty, it's OK if you can accept that.