MDC -- might have to splice some .. also MT 50's might be good for these
http://www.spookshow.net/freight/athearn50seico.html
http://www.spookshow.net/freight/athearn60autobox.html
1st car- a pair of MDC cars would be the way to go, they have a 12' plug door rather than the 10' plug door on the MTL car, and more importantly, they haven't been vertically compressed to overcompensate for the jacked-up bolsters on the MTL car. The picture is too small on my phone to see if the prototype has the same X-panel roof on the MDC car.
MDC FMC plug door car is Plate C car with a 12' door opening and would be a much better starting point than the MTL car that has been squished down to overcompensate for the jacked-up bolster height and only has a 10' plug door
MTL plug door car is closer to a Plate B car (when it's not jacked up) with a 10' door opening.
2nd car - The "droop" sill tells me that this is an ACF-built car, and the car appears to have a flat roof (likely diagonal panel) rather than a peaked roof, but the resolution is a tad small on my phone to say for sure.
For the starting point, it may be a toss-up between the Atlas Trainman ACF 5300 or MDC plug door car to see which pair of spliced cars would require less work to match the sides of this car (before adding styrene "waffles")
Atlas 60' ACF auto parts cars have a flat diagonal panel roof that may (or may not) be useful for this car.