There's not really a retail parts source for the 1930's games; have to scrounge from other games, collectors, and more often than not, fabricating your own. A lot of the stuff can be hand-built as needed. There are some repro parts available for the Rockolas though (e.g., Jigsaw, World's Series, Army/Navy).

Makes them a bit more of a collecting challenging, but they also didn't have a lot in them either.

A lot of the 30's games require replacement parts to be fabricated by hand, or some creative substitutions.

Some spring steel strips might be usable to fashion those particular springs (for example). (I suspect those were made from spring steel in the first place.)