The model A wheel needs to be mounted by the lug bolt holes to be balanced on a modern machine (most modern machines mount the wheel with cones in the center hole --which is how most modern cars center the wheel), I and many others here have used a spindle, and hub with lightly oiled bearings to do a static balance.
Sometimes trying different positions of the tire on the rim can balance the wheel without weights, using corn starch, or talc to lube the inside of the tire so the tube doesn't stick is also a good idea.
A model A is not as sensitive to balance as a modern car because the wheels are narrow and the suspension is heavy.
If you do not mind the look modern weights will fit the rims.
Many wheels have never been balanced, and there is probably no need if you do not intend on driving over 40.