Can one physical port have two ip address?

[TheBlueBlues]

Hi guys, my company is using Checkpoint PB-20(5200 appliances) as the firewall and router.  We have changed a new network line and now we have one more public IP address to use, but we don't have more spare ports now.

Now a new request is that we want to do a flow distributing by the destination IP address. For example, we have 1.1.1.1 and 2.2.2.2 and want the traffic to 11.11.11.11 use 1.1.1.1 as the source address, and all other traffic use 2.2.2.2 as the source address. It's easy to do if we have two ports but unfortunately, we don't.

 So is there any way we can do this flow control on one port (connect to CE device)?  Any feedback you can give me on this would be greatly appreciated. Thanks in advance!