Let me suggest that you look around the web -- google images maybe -- for units that look pretty much like your Reliant. Many of these tools have parts in common, and if you find one that appears to be a twin for the Reliant, there's a fair possibility that parts will match OK.
I recently bought a 25-yr old PSI dust collector at a yard sale. Grizzly makes one just like it, so does Jet. So look around hard and you may find what you need. Good luck with it!