Vintage Synth Repair

I picked one of these up a few days ago. It works good, but its 
physically pretty beat up. Nine of the sliders are broken and all the 
knobs are missing, the sliders work you just cant use them with the 
cover on the synth. How would I fix these up? I believe they should be 
the same as the Crumar orchestrator,multiman,performer sliders. I also 
have one key which does not sound, my lowest E#, it does output a 
small thump sound when you press the key. How can I locate the problem 
here? Also, if anyone might have some information at all about this 
synth I would love to know. I cant find anything about it on the net 
but one small fuzzy photo at the univox site and a guy playing it on 
youtube, but the label is Crumar on the video. 
Thanks,
-michael-