YMMV. I was able to successfully purchase 4 packs of these for $1.19 each and used code Family5 to get $5 off the delivery fee. I believe the max number of packs you can buy is 10.
I can confirm that San Francisco and San Jose should have these in stock.
You need to have at least $20 in your cart to check out.
Put in your zip code and search for Red Bull. Good luck!
https://primenow.amazon