Short (per se) is not a problem in terms of weight-carrying ability (until you get down to real "pony" sizes)... in fact, stocky strongly-built short/modest sized horses generally do BETTER than real tall ones, because they are more inclined overall to soundness. You have to remember that, for a given "build", a 16.2 h horse is already carrying a much higher load per square inch on his legbones/tendons/hooves than a 14.2 or 10.2 one is, purely because of the way things scale. So larger horses are already closer to their 'load limit' just from their own weight and moving forces.
A sturdy, even somewhat drafty-looking, 14.2 horse is usually GREAT for a larger rider (also for a longer-legged one), plus you have the great advantage of not being quite so far off the ground either
and their soundness and longevity is on average better.
As far as the "we don't have a saddle so you can't see him ridden" people, maybe they really DON'T have a saddle is all, HOWEVER since you do not want to buy a horse you can't see ridden, it just rules him out, plain and simple, same as if he lived too far away from you or whatever. I would NOT count on just bringing a saddle -- even with western saddles, it is just not that easy to ensure that you get a decent fit between saddle and horse, and quite honestly I think this one should just be regarded as a "pass" (and not just for that reason)
Pat