It would appear that Google's Chromecast Ultra has already hit some Walmart shelves prior to the device hitting other retailers and Google's own online store. The new UHD compatible HDMI streaming dongle was seen at a Walmart over the weekend it seems, although the image shown on the Reddit post merely displays the price tag of the device and not the actual hardware. Having said that, there's actually no way to know if the stores already have them in stock, or if they are simply placing the price tags up for when they release the units. In fact, that's more likely the case, as the Walmart website does have a device listing for the Chromecast Ultra, but it's only available in pre-order status, so it won't be shipping just yet.
Still, this is more than what you'll find over at the Google Store, as your only option is to join a waiting list which means you aren't able to pay for it through the pre-order yet. According to Walmart's website, the Chromecast Ultra will begin shipping by November 10th at the earliest which isn't too far off from now, so those who want to get a head start on grabbing one can at least pay for one through Walmart online, or if you live in Canada you can pre-order the Chromecast Ultra through the Google Store.
Walmart has the device listed for $69 which is the same price at the Google Store and other retailers who will be carrying the product, although it's entirely possible that it will pop up somewhere for more than that online if stock runs low once it's actually available. In addition to Walmart you'll also be able to pre-order the Chromecast Ultra from Staples and Best Buy, and eventually Target as well. While Google themselves don't list the ship date of the product, if Walmart's date for release is correct then it will only be a few more weeks until consumers start seeing these show up at their doorstep. If you don't have a Chromecast yet and you do own a 4K TV, the Chromecast Ultra will allow you to stream and enjoy 4K content, as it supports 4K playback, and it also supports HDR (High Dynamic Range), so there is a benefit to having this model over the standard version. Of course, if you don't have a 4K TV, the standard Chromecast is still very much available and it costs $35.