It looks like you purchased a very nice set, and you plan to run it.
Were the set mine, I'd put away the type "L" transformer, and run the train with something more modern. Those old transformers just aren't made with the same safeguards are more modern models.
According to the reference book I grabbed, your transformer is either a 50 or 75 watt model.
Many, if not all, prewar transformers put out up to 25 volts. I am not certain about your "L" transformer.
Regardless, a 259E shouldn't need the voltage to go that high.
There are a wide variety of transformers you can use.
Most newer transformers (1946 and on) put out their maximum voltage between 18 and 20 volts, which should be enough for your train set.
I prefer transformers with plastic cases.
My favorite medium sized model is the LW. You could also use a 1033, 1044, or the 1034 that your seller referenced.
Going larger, there are the KW and ZW.
I would not go smaller.
Lionel also made some modern transformers with metal cases.
These would look better with your set, but I don't like the metal case models because of the remote possibility of the case beinging electrified.
Suitable models include the "R", "S", "Q", "RW", and "SW".
Finally, there were two models that have a plastic case, and go to 25 volts. These are the "V" and "Z". They are good models too.
