Transformer for a Lionel 2141WS set

[Charlie B]

Hi Lionel guys, I have a question I know one of you will be able to answer. I just got today a 2141WS "O" set that is exactly the set I had as a 6 year old. It does not have a transformer and I would like to have the same one that my dad got for the set in 1949. The set has the 671 steam turbine with the whistle tender, operating milk refer and log dump as well as caboose and a hopper car. The transformer I had was not a monster but had 2 knobs, one for the whistle which had a spring to return it. If I have a number I am sure I can find one somewhere.
Merry Christmas
Charlie