the 7 1/2 shouldnt be all that much bigger, you could always get some damp paper towel, and wet the inner head band lightly, and wear it till it starts to "shrink" or fit.... or you could go the extreme route: get a spray bottle, turn it to mist, and mist your fitted till the whole hat is damp, not soaking wet... the wetter the worse (the longer youll have to wear it, and youll have to be more careful when drying it)
if its damp enough, the water will start to tighten up the wool. Youll have to wear it around the house long enough to start to take shape. i've done this on several of my fitteds, not 1 of them is ruined from going about this process.
important: when wetting your fitteds, please be careful of the brim, the brim will get extra flexible with the addition of water, so if you dont want a "curved" brim, dont touch it all that much while its drying... BUT keep in mind the brim will "warp" a lil bit. Since the head band, and brim sewn together, if one changes shape, the other one will. so your brim will start to take a natural shape, according to your head size, and cap size.
i do not suggest doing this on fitteds that are 2-3 sizes too big for your head, nor do it on fitteds too small for your head.. youll end up fucking up the hat.
ill try and post some pics of the hats i have fitted, and the hats that are still pretty fresh.
hope that helps you guys
ohh yeah almost forgot:
always check the tag on the inside of the fitted, usually sewn to the back inner head band. to see what material it is, if it'll shrink, or not...