Kevin,
The bike I took down in a 1600 mile round trip and still have is an XR600 (1993). After the proper prep, neither me nor my buddy, who has the same bike, had 1 problem the whole trip. Not even a flat tire. We had no car, just the bikes and we were rough on them.
My bike has a "Baja Engine" kit on it which pumped it up to 660 and it runs fantastic on crappy Mexican gas. However, when I take it up to the Sierras it has some air / fuel issues because it is not set up for that.
My reasoning for buying that bike was the fact which you mentioned, there are a lot of parts down there, not to mention that, as far as I am concerned, Honda simply makes the most reliable bikes on the planet.
Some friends of mine have the CRF bikes and those are absolutely great bikes as well.
Good luck with the bike hunt.
Glad you are back on board with the 80.
Life is good.
Jeb