Instead of using a paid tool, you should first try an easy manual trick. It's easy, simple and as effective as a professional tool. You can read this blog post for detailed information: wordpress.semnaitik.com/2014/05/24/convert-mbox-to-pst-manually/

In this blog post, you'll learn how to import OLM files' data to Windows Outlook.
  • First you need to create an IMAP mail account (Gmail).
  • Then setup IMAP mail account with Outlook for Mac.
  • After that, you need to create a Gmail label to synchronize IMAP account and Outlook for Mac.
  • Then you can move emails and other mailbox content from OLM files to IMAP mailbox folder, and then you can import mailbox content from IMAP folder to Windows Outlook.

Before you can use any paid tool, you must try this manual trick. I hope the shared information would be helpful here.

Thanks and best regards.