This is a #2630 balance rod from a Clearview window. The company is out of business. The windows were installed around 1979. Looking at your website I think the series #351 with the top and bottoms 19-002 and 15-002 will work. Might not be a perfect match but close.
Tom from SWISCO responded:
March 30, 2017
Thanks for posting! If your nylon caps are the same size as our 15-002 and 19-002, I agree that the Series 351 would be our best match.