We are using Etherchannal to connect switch(non-stackable) to 3750 switch stack. Do Etherchannal receiving ends have to be on same switch of stack?

We are using layer 3 switch 3750(standard image) to connect all VLANs. We need to enable one PC to receive broadcast from server that is on different VLAN. How can we do that? Multicast? but it sounds like 3750(standard image) not support multicast. ...