Hi Mickey,
> 1.Use of middleware; we don't have PI but some proprietary software which takes quite some time to integrate on such a short notice.
Let me suggest the SAP Business Connector as one option. Perhaps it can be used here. It is a middleware like PI, but free of charge and more "lightweight". Installation files and documentation can be downloaded from SMP: https://service.sap.com/sbc-download
On the SAP BC you can create custom Java or C/C++ functions which get triggered by RFC calls from R/3 and which perform the direct socket communication with the external server.
Installing and setting up SAP BC for RFC communication with the SAP server is a matter of minutes. Then you need a day or so to learn how custom development can be done on it. Let me know, if you have more specific questions as to how to try a POC.
Best Regards, Ulrich