I’d stick 11 quid a month in a pot(*), personally. My first cat lived to be 18 and the second was so terrifically ill that keeping him going would’ve been cruel; I’ve spent *considerably* less than £1200 in vet bills in that time.
I have inherent distrust of “cover” generally, you pay loads each month to cover your cat, credit card, teeth, washing machine etc, then when it comes to claim there’s always some bloody loophole which means they don’t pay out.
I have car insurance (natch), house b&c insurance, that’s it. Everything else just comes out of the pot on demand; there’s so much that needs cover that you can’t possibly afford to cover it all, no forms or faffing about.
I appreciate that it’s not a good plan for everyone, but for me it works.
(* – kitty? Please yourself.)