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Streaming Stick 4K+ 3821 | Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X
Just to clarify, NowTV in the UK "white labelled" Roku, with branded devices and a separate channel store.
Older devices (mostly white coloured) have been de-supported, don't work anymore, and NowTV doesn't sell any devices anymore. NowTV sold both boxes (standard IR controller, should work worldwide) and sticks (wireless remote, may not work), with remotes coloured white and black, and Now/Sky oriented channel buttons.
NowTV (UK) was set up to be the budget priced streaming version of satellite broadcaster/ISP Sky (part of Sky's long term transition from Sat to Stream). Sky was taken over a couple of years ago by Comcast (Sky News was spun out into an arms length enterprise as a requirement of the takeover.)
There is an unrelated NowTV channel in Roku US Channel store.
NB UK to US shipping via eBay global programme or independently is a lot cheaper than US to UK, totally viable.