This is not Amazon, it's Lidl, so of course you can't reserve it online
please share the link. You can find Lidl everywhere, but not Costco.
looks like it's this: https://sharpconsumer.eu/product/bl2/50/50bl2ea/
Android inside a TV is always a very bad idea. Android externally for example an Nvidia Shield that's how you do it properly. Android in a £279 TV that seems like disaster, I can't see it working out well but good luck if you try.
I got a feeling that you are going to get what you pay for here... Android TV isn't that snappy on an 18 month old Sony we have (55") so I can only imagine what it's going to be like here. Maybe spoiled myself with the king of Android TV, the Nvidia Shield right enough (owned all models except that tube number they've spat out as the "budget" option now).