I was told that the folks at Maiback can supply parts for the Oliver 60.  I haven't done busness with them yet.  I hope they have what you need.
<!-- m --><a class="postlink" href="http://www.agcocorpdealers.com/MAIBACH/default.cfm?PID=1.4">http://www.agcocorpdealers.com/MAIBACH/ ... fm?PID=1.4</a><!-- m -->