The early coronas are indeed tough cars and a delight to own. Im more familiar with the RT40......well familiar means I just know what they look like.......not too much in the tech section.
I think you must post pics here so members can guide you better. What model is it?? A late sixties one????
From the limited things I know about them, (seen one RT40 being rebuilt at the garage which restored my 68 Beetle) Ihave also observed that parts for these cars are unfortunately cheap aftermarket crap. This is due to the fact that most of these gems are now sadly owned by cheap blokes who just consider them ''just another old car'' on which they should not ''waste'' money.
So I think the first thing to do is just inspect the car thouroughly, make a wish list of parts and run down to the auto market and see whats available. Hopefully members here may be able to help you locate original and rare parts.
Good luck with your quest!! Ah! one more thing!! If properly restored, this gem would easily outlast the brand new crap coming out of the factories now!!