Before giving them up, you might want to try this:
put on a pair of socks
force the shoes on (this might be tough and require a shoe horn)
while standing, use a blow dryer to heat the shoes (not so close as to damage them, and avoid the seams where the shoes connect to the soles - there might be glue that could melt or give way)
walk around until the shoes cool COMPLETELY
At this point, your feet will likely be screaming for a break and you will be delighted to remove the shoes. Take off the socks and give your feet a break for a while and then try the shoes on again. Suede stretches quite easily and this really ought to give you some extra room. You can repeat the process as necessary.
But like it has been said, it is difficult to change the length of a shoe. The footbed itself cannot change, so only stretching the upper can be done. If that will not be enough, then it is a lost cause. But this method really works well on pumps in my experience.