My local TRU in Raleigh had 1 each of the red and blue Nerf Rival atlas. Well, the blue one is gone now *whistles casually* but I can vouch there was a red one left when I left the building. There were no Kaos units that I could see though.
It also might be worth your time to watch the Toy R us website and try to nab a screenshot of the rival blasters in their online sale (actually ending today, I just noticed halfway through writing this, better hurry if your in a better time zone XD), where the Atlus and Kaos have been listed for a bout 7-20 bucks cheaper(though sold out and on preorder). They told me they would price match their own online price, as well as their competitors though. Since I’ve begun randomly checking them a few times a day online, they would occasionally not show up in searches. I speculate they were randomly restocking online and then selling out, where after a while they would be removed from visibility again. I should also note TRU ships for free on $19 dollar plus orders, should you be lucky to spot them in stock online.
When I got to the shelf, they actually had both rival blasters above and under $26.99 USD signs for the Nerf Apollo, and it looked like staff had put them there. They did not honor that price, but they DID honor the 32.99 online sale for me on my word alone, despite not being able to pull up the price at that moment on my mobile device. The in-store price was listed at 39.99 at the time, so they had to override the current in-store price, so make sure you have a screenshot of the sale on your mobile device handy.
Don’t seem to have access to the edit button from my home PC, but here an update:
They are back online and even cheaper at the moment I posted this. The same blasters are listed more than once in the search below for some reason, and only some of them will ship to home from online. If they aren’t in stock online, or you have a Toys R Us nearby, get a screen capture of the sale on your phone and the store will honor their own online deal: