There are actually 3 different SKU’s but they all look to be the same bulbs. I just bought some at my Local Lowe’s. Others are permanently out of stock. Some of the local stores do show these as ship-able.
At my store they were stocked both in the Lighting section (Row 1) and the Home Automation section in the Link display (Not the Iris, Row 12).
Agree on $15 being the normal price. This is what I have paid for the three I have picked up over the last 6 months.
Just be prepared for possible oddities since the last Firmware update hit the ST hubs. I have one that likes to randomly turn on in the middle of the night. And two others that just like to randomly stop responding to the hub and either refuse to turn on or turn off without a manual power cycle. Prior to the last update, they were solid.