20 years old are legal to import. I tried to buy one last time I was in Guadalajara, but we couldn't come to a deal. (He seemed to think a "gringo" wasn't serious to start with, then wanted too much..
The OP's truck doesn't look right somehow though - wrong headlights for a '94 (those are '98-'00 headlights) and that rear seat doesn't seem right. I'd need a picture of the roof to tell you definitively - the Latin and South America trucks don't have a smooth roofline - they look like the extension was "tacked on". They are built on a SuperCab chassis, so you can check if the wheelbase is 125" (more/less) or not too.