Since your car came from CA, does it have the BAR sticker, which makes it smog legal for CA?
I have been buying my parts from John Price www.johnpricerallying.co.uk over in the UK, communication is a lot easier. John's pricing is competitive, but the shipping is expensive. I have also purchased a few parts from 3S development www.3sdeveloppement.fr.
There are a few R5 owners here on the West coast, so getting information is good.
Let me know if you have any questions and I will try and help.