Trainguy Ken - Nice find on the Marx windup set!
Greenberg's can be confusing when it comes to mechanical Marx locomotives... but Marx mechanicals can be confusing all by themselves. The following is what I have been able to determine from my research on Marx mechanicals concerning the 897/898/833 and 591/533 locos. Marx came out with the #897 prewar, and that number was used for both the electrical and mechanical versions of the loco with the lithography on the body. I have seen period ads from 1941-42 for mechanical 897's:
Postwar, Marx used this same basic body for electric and mechanical locomotives, but they were just plain black, no lithography. It is my belief that the 898 designation is for the electric version and 833 is the proper designation for the mechanical version. From period ads I've seen, I believe that Marx produced the 833 from 1947 through 1953, although I do have one ad from 1954 with a set led by an 833. However, I suspect that Marx was getting rid of leftover sets through that retailer at that point, since the 591/533 had been introduced by that time (more on that in a minute). I've documented six different variations of the 833, not including the 897. Below is a common set with one of the simpler versions of the 833; Marx was notorious for taking details off the locos in order to meet a given price point for a retailer. Note that the 833 doesn't have handrails or side rods - it came this way from the factory:
1953 is the last year the 833 is seen in most retailer ads, but it is the first year that the 533 makes an appearance. Again, I believe that 591 is the proper designation for the electric version, and 533 is proper for the mechanical version. Note that the construction of the 833 is considerably different than the 533. The 833 is all stamped steel, whereas the 533 has a stamped steel body with a plastic piece in front for the smokebox door/pilot. I believe the 533 was cheaper to produce, which was very important in keeping the price low on the entry-level mechanical sets. I have retailer ads from 1953-58 showing various 533 locomotives. The 591/533 was also sold in a battery operated version powered by two "D" cells with a switch on the top of the boiler - I haven't figured out what the Marx number designation would be for this version. I consider it an honorary windup since those sets came with 2-rail track - haha! I've documented ten different variations of the 533 (mechanical & battery). Here are a few variations, with a couple of battery operated locos at the top, mechanicals below:
I won't go into sets or possible sets, but I will say that I was unable to find a set exactly like yours in the ads . That's not to say that it isn't a valid set, and it seems that Marx didn't have any qualms in substituting cars to get sets out the door, either. But, it is a nice train, thanks for posting it!