Is WD101EFAX discontinued? How to get 10TB 5400 CMR drives now?

I recently made an order from Newegg’s marketplace because they had the above model for sale. Instead I received a WD101EFBX which AFAIK is the 7200 version of the drive. I complained and they said the EFAX is discontinued and this is what is sold in its place. The WD store only seems to have 7200 rpm versions of the 10 TB drive as well. I Googled the model and “discontinued” but didn’t find anything confirming this. Is it just a shortage or is it really discontinued? If discontinued is the 7200 noticeably louder? Or is there a new 5400 10TB model coming soon (WD102EFAX?)

AFAIK both versions of the disk, WD101EFBX and WD101EFAX should be available but stocks may vary and the price for each disk is the same.

Are you using this disk in a NAS box?

Yes. This would be the 4th disk out of a 4-bay NAS. The others are EFAX.