To convert MAC OLM to PST format, use more reliable software OLM to PST Converter Tool. The software exports entire database including your emails, contacts, attachments, journals, to-do list, notes and tasks and etc. It supports all updated MS Outlook version 2000, 97, 98, 2002, 2003, 2007, 2010, 2013 and 2016 and all updated Windows OS version.
Reference link -
http://www.tools4recovery.com/olm-to-pst-converter.html