EML to NSF Converter is best option if you want to recover your Outlook PST file, Just follow simple steps and convert EML to NSF. First of all you need a tool for converting EML to NSF. You can try this tool:- http://www.nsfsecurityremover.com/eml-to-nsf.html
I have used this tool with my large size EML files and simply browse your EML file and export into NSF file format.