Wow, what an amazing experience on the airstrip, crazy! We did the same thing, brought parts into Mexico and had some repairs done in Tijuana. We were fortunate that our parts weren't expensive and we had a young kid go in the back to look around (while the top was down :).
$1400 is parts? and they got you for the import fee? Crazy. I bet not a word is spoken when any of the baja races go on...Anyway, I've been down there numerous times and fortunately never been shaken down for money.