Erm...cory can basically reach 4-5cm. Mine's a C.Elegans
Well any type of cory will do as they all behave in the same manner. Their mouth is to small to try to eat anything thats still alive and kicking...hehe
They do eat BW for your info...so if they do bump into your shrimplets...heheh who knows.

You can try out some cheaper ranges that are abundantly available in the lfs like C.Panda, C.Paleatus, C.Aeneus, C.Trilineatus, C.Sterbai and so on.
You can go to AI to hunt for those a little more pricey ones that usually turns up there. Sometimes you may bump into something pricey too. If price is the main drawback, then the usual C.Panda & C.Aeneus will be more than fun for the price they go for.