same IP subnet network communication through srx300

Hi,

Here is  2 buildings with same IP subnet but different gateway. We need to connect SRX300 in between 2 building and exchange data between certain nodes(node IP are diffrent at both location). we can not change IP subnet at both end(all systems are in production).

Building A --> 172.16.0.0/21  Gateway 172.16.0.174

Building B --> 172.16.0.0/21  Gateway 172.16.0.200

All nodes are connected on respective L2 switch at respective building. We could not connect A building nodes directly on B building switch. there are different application running at both location.

Can we configure nat on srx to communicate same subnet IP or any other solution. i also want to apply security policy for source and destination IP/node.