Hi SanjeevT,
I would like to suggest you use PST Capture 2.0 for exchange 2013 and import it to mailboxes. There is no limitation on the PST size you want to import, it’s easily injects PST data to primary or archive mailboxes on your on-premises Exchange Servers or Exchange Online.
Please refer to the blog what’s new in PST Capture 2.0?
For more information about Microsoft Exchange PST Capture 2.0: http://www.microsoft.com/en-us/download/details.aspx?id=36789
Thanks,
Shyamal