rear frame rails

i have a 79 Camaro I am building into a race car (just bought it and wasn't able to see the underside of the car) - I just found out the right side frame rail is rotted away and needs replaced - I can find a partial section of it but not the full section - anyone have any ideas where to find the full rail - also how do the leafs mount in the front - car currently has no leafs or rear end in it

This is one possibility:

http://www.jegs.com/i/Competition-Engineering/247/3032/10002/-1?CAWELAID=1710788141&CAGPSPN=pla&CAAGID=44693592161&CATCI=pla-221938240151&CATARGETID=230006180039216954&cadevice=c&gclid=CLTblaWH4tMCFRSewAodqLcEJw

If the chassis will be raced, it may require subframe connectors at a minimum, and possibly a tube cage for reinforcement.

Yes I have seen those but according to the rules must be stock ... Might contact them to see if I can use these or part of these ... The car already has a complete cage as well

And I will need to tie the subframes together as well