A couple of weeks ago, I overheard local sellers mentioning of gradual price increase as the stocks available locally depletes. I personally didn't think it would get to the stage of SOLD OUT locally.
If you are highly suspect of Overseas China Sellers, then rest assure the Overseas Shopee seller Linglang comes highly recommended. Tx3 Mini and Tx3 S905X3 should still be available as mentioned by AVFAN.

The price is only a little bit higher, but the After Sales Service provided is very satisfactory. Do review the previous customers comments who also highlights this fact in their review. I highly recommend the seller for those with zero knowledge of Android TV boxes.

There are others who prefer cheaper, and I don't fault them. These are buyers with prior knowledge of Android boxes and how to play around them.

There are those who wants a plug and play box, and again I won't fault them. New users with zero knowledge usually opt for a ready made item. However that is because these buyers didn't expect sellers to guide them step by step, and most times sellers who peddles "Fully Loaded" boxes don't offer much after sales service. Rest assure at some point in time, purchasing android boxes or even Mibox S or Nvidia Shield of FireTV, users will require to learn how to install, update and navigate apps that isn't available in Google Playstore.

And lastly there is the issue of Legality, MCMC. I think AVFAN gave a good explanation above.
The android boxes with Android OS is just another Android Phone without Screen but has a HDMI output.

The MCMC certification paraded by some Android Boxes is a 'hoax', a 'con', a 'scam' to trick unknowing consumers into thinking they are legally buying Digital Media Content for a one time fee of RM350 ~ RM800. I have written on this subject in a different thread.

Those who like to know more about One Time Pay Android Boxes so called legitimate MCMC SIRIM approved boxes, I submitted a writeup on them in another thread.
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