Tillotson MS 113A looks fairly complete. I believe Ferguson Poole may have some minor items. Bob Grubb may be able to help.
1940 was 80 years ago on the other side of a wold war. My experience
in hunting down parts for MS113A makes me believe the best
and perhaps only source is another MS 113A or a closely related
model. Float bowl gasket can be made using accurate ruler and drafting
compass measure carburetor bowl opening, then transfer and mark
gasket stock.. The fuel inlet gaskets may also be reverse engineered.
Where there is a will there is a way.
Good Luck