Those latches are part 5680BX right, and 5679BX left. But about the only way is to adv. on-line or check eBay.
Good place to put a free classified is MTFCA site, free to place add, and put the picture of what you are after. Link below:
http://www.mtfca.com/cgi-bin/discus/show.cgi?3487/3487
These photos should help. The right one has a piece of baling wire looped on it, the left one (drivers' side) shows best, the little cutaway triangle (pyramid) is the hint, and the hole for the door panel fastener socket for the ringed nail used to fasten the cardboard panel.