I've realised my shoes are too large, suggestions?

Okay,

So having spent much of the past year rather broke, I came into some money and decided to go out and buy a whole new load of clothes.

Included in this were some Barkers tan brogues, size 10.5. Now, I've currently got a pair of Hudsons which are 10.5 and have always bought 10.5 (10s are that bit too small on one foot).

I tried them on during a busy day of shopping and they felt a little stiff to get into even with a shoe horn, but once in they felt fine.

However, having worn them 3 or 4 times since, I've noticed that my feet don't nearly fill them out. They've already started to crease about half an inch-to an inch from the ends, and against my other 10.5s they are quite a bit longer.

In terms of wearing, now they've worn in a little, they aren't painful to wear, but I can tell the creasing, where my toes are will increase quite a bit.

Obviously, I can't take them back now because they're definitely a bit worn.

What do you suggest I do?

Funnily enough, just after I posted this I was looking through a bag of stuff my Grandad gave me today (not as presents, just old shoes which he can't wear anymore). He said 'I'm a 10, but you can try them on. There's a brand new pair of Barkers patent loafers - size 10 - they fit perfectly.

I'll know for next time.
I shall buy some leather insoles - are these the sort of things where there are good ones and bad ones, or can I pick up any?

I'm afraid I can't really afford to donate a pair of shoes that set me back this much, nor can I afford to buy another replacement pair.

Thanks for the advice, I'll grab some of the the better ones when I get back into London.

Compensate with insoles and/or something else as well?

Thanks for all of the advice, shall feedback when I've got the insoles.