In reply to AJM:
Are Matterhorns leather or plastic? If they're leather, read on...
A friend of mine had his boots stretched by Rock+Run in Ambleside last year over some bent bar type device, just by putting pressure on the boot with rounded bar inside.
Now, I've heard mixed information about this technique, i.e. it can weaken the stitching or bonding to the sole. It can also stretch the leather too much and cause that to be weaker too, but My mate he says it certainly helped his feet as boots don't feel as tight anymore.
A decent outdoor shop selling boots should be able to do this for you, depending on the boot construction.