They are obviously New England Patriot slippers. They appear official as they have the NFL hologram and were sold by FOCO UK
I would like to know more about the year they were sold and any other info. Google searches, reverse image searches yielded no match unfortunately.
I guess the best I can say is that they’re made after 2008 and not before, because that’s when the NFL logo changed.
I also think the team itself switched from a cursive to a more block-like font more recently than that but I can’t put a finger on when the font changed exactly.
Thanks to you and the sibling comment here. Timeline helps narrow things down. Not being much of a sports fan I had no idea about the logo changes.
The new Patriots logo font appears to first appear around Oct 2013, going by the archive of their Pro Shop website.