My feet are huge (size 13 and on the wide side)
HAHAHAHAHAHAHAHAHAHA!
Only such problems
. Try being a size 17-21 (depending on brand).
That being said, for the last 5 years I've been buying Ecco that's one or two sizes too small (they don't make 'em any bigger) and they stretch to a perfectly comfortable size in around 2 weeks.
So if you get a size 13 (equivalent) Ecco, you'd likely be uncomfortable for a few weeks and then very comfortable for a long while. Worst case get it somewhere with a good return policy.