I don't think they're getting dedicated hooks this go-around; I think that was the reason behind them having normal United packaging?
When Ferak hit our nearest Walmart, I scanned it with the Walmart app to see what it's listing read like; seems like "Star Raiders" is the keyword phrase to get them to pop up on the app. Then, if you check the others availability for "Pick Up in Store", if your store doesn't have them, it will (in theory) check for them in other nearby stores. I was able to get Lockdown and Road Pig this way.
Filch, on the other hand, was pure right-place-right-time happenstance. It does seem like they're getting out into stores now, so good luck to those still hunting them!