It does kind of suck about the rear derailleur i have asked the family i got it from but unfortunately the original must be lost in the sands of time.
I wouldn't worry too much about the derailleur etc... they weren't exactly the most high tech doohickies to ever grace bicycles: http://www.disraeligears.co.uk/Site/Renak_derailleur_%284th_style%29.html
@Soul started
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I wouldn't worry too much about the derailleur etc... they weren't exactly the most high tech doohickies to ever grace bicycles: http://www.disraeligears.co.uk/Site/Renak_derailleur_%284th_style%29.html