APA Open Community

Try Joe Braga, Engravers Choice, Mission Viejo, CA

714-949-355-4000; he works on Xenetech's

That is a Xenetech 912.  I wouldn't go to the trouble to replace the left cover. It was quite common to find 912's w/o the cover.  It had to be removed to change or service the 912.  Often, user's found that there was no disadvantage to leaving it off.  
However it appears that it does not have a belt; that is available from Q1 Engraver's supply and will be required if burnishing or plastic engraving is needed.
I suspect you've learned that Xenetech is no longer in business; limited support/supplies are available.