Yes, I have a spare router, but I am just a customer like you, as is pretty much everybody else here, so you can’t have it 😛
Yes, the Now router is a horrible device, with all the range of a thrown anvil. And it’s the only one they do 😢
You best bet is to source a Sky SR203 router off eBay; cheap, no reconfiguration needed, uses Sky/Now’s slightly unusual MER 61 protocol, much better wifi range than the Now router.
You can, these days, find more of the mainstream routers with MER 61, and they are more versatile. But they will need configuring; the Sky one is a simple swap, and entirely suitable for most purposes.
You knew Now must be cheap for a reason, didn’t you? Well, the router is where it starts 😛