As a British person, CeX is pretty cool but it's really the only larger tech chains in the UK if you don't want to shell out a kidney as opposed to just buying online. I think they're also all across Europe - saw a few in the Netherlands a few...
I may try the new ram site, and download more RAM to my Switch. Not sure if ddr3 is the right ram
for it tho. Edit- no it uses floppy Ram, just like @AncientBoi