The Lionel Scout set was manufacturered from 1948-51, but that doesn't mean that some left over stock wasn't sold in 1952 or later. The Scout set is notorious as being one of the cheapest and lowest quality sets Lionel made. It can't couple with other Lionel trains and the engine's motor is quite problematic. Because of it's reputation Lionel stopped making sets under the Scout name, but did make chepaer sets after that.
The Scout is still a nice looking set though and can be found quite cheaply. The Scout is anything but rare and is quite easy to find. You might find a set at a store that deals in postwar Lionel trains or at a model train show if there's one in your area. However, your best bet would be to search ebay. At any given moment there are many Scout sets listed. You could probably find a good one for less than $100.
The contents of a Scout set are:
10012-4-2 type steam engine
Tin "Lionel Scout" tender
1002 black Lionel gondola car
X1004 orange Baby Ruth Candy boxcar
1005 grey Sunoco tank car
1007 red Lionel Lines caboose
However, you mention that you are guessing that it's a Scout set. Lionel made many, many train sets with black steam engines. Also, many other Lionel sets with cheaper plastic steam engines are referred to as Scout sets, even though they are not the original Scout set.