The MTH Z-1000 may be in your range. They are about $100 new, less used. 100 watts, good quality. Truly excellent little transformers and the absolute best in that prices/size range. Should have no problem running modest Postwar trains. Been there, done that on my own layout!
I love Postwar and Modern trains and run them all - Postwar, Modern Conventional, MTH PS2/3 and Legacy. I would, in no way, use a Postwar power source. I don't care how rebuilt it is, I just don't trust it. Modern gives you piece of mind and, most importantly, new circuit breakers and related protection. If you try running modern trains with a Postwar ZW without additional protection, you'll be cooking engines if there is a derailment.
I used MTH Z-1000s for years. I have one in storage as a "back-up". About a year ago, I replaced my 10+ year old Z-1000s with three brand new, state-of-the-art Z-4000s. Didn't need that much power but it is good to have, not to mention a warranty and the newer technology.
I've seen plenty of layouts running Postwar power sources. All of them are hot enough to cook on after a few minutes. You'll never get a modern transformer that hot, at least I've never seen it after 25 years in the hobby including 11 years of modular club railroading (where you sure as hell see the "extremes").
