I'd advise against an engine that smokes anyway, basically what they do is vaporize oil and pump it out thru the stack. Then guess what? The oil condenses onto your track and everything else. Makes quite a mess.
As for engines, the Spectrum engines are really great, I have a couple 4-6-0 high-boilers and a Russian Decapod, truly beautiful little engines. Also in your price range would be Mantua, I know the old ones are great engines, I don't have any experience with the new ones made by Model Power. If you go to a train show you can find old Tyco steam engines that were made by Mantua, the price is good and they'll pull the sheet rock off the walls. Just stay away from the one with the motor in the tender. IHC also makes some real nice engines, they have a couple types of Pacific (4-6-2), one standard and one semi-steamlined. They're not as nicely detailed as the Spectrums but they're good, solid engines.