the years you have are correct. the number of the sets containing the tender varied over the years, but the engine/ tender pair is more desirable. as far as condition, the best thing you can say about it is that major parts do not seem to be dented or damaged, but it is far from being in good condition cosmetically. and if you tried to replace the missing parts, they would be too prominent next to the finish as it is now. this would only be desirable as a candidate for restoration.
assuming you do not have any box, a few hundred might be a bit overoptimistic. i would sell the tender separately. you'd probably get just as much for the tender by itself as you would for the engine and the tender together. then sell the engine for parts or disassemble and actually sell the parts.
this is a long shot, but check the drive wheels with a magnet. very few were made with cast iron wheels.
