if you're talking about the mid-receiver where the slide attaches, this is a common problem with plastic receivers on the cansoft version of these guns. i have a baby hicapa cansoft version and part of the plastic that holds the beavertail in cracked off. its still functional luckily, but I have since tossed it in the closet and have learned my lesson regarding what I will and won't buy in the future.
the grip and the mid receiver actually come apart. regarding if you can get a new mid-receiver, I've never seen them for sale by themselves. your best bet would be to find a whole used gun functional or broken in the classified and scavenge your parts that way.