iPad from Ebay rather than Apple

Help

I want to purchase a new 9th Gen 10.2in iPad for my mum for Christmas however due to material shortages, Brexit, Covid or the fact the world is ending I cannot purchase one directly from Apple or any reputable seller in the UK whom can deliver it in time for Christmas.

How dodgy is it buying tech online like this ? How come they have what they call UK stock when nobody else seems to have? Any recommendations on an alternative means of getting one?