Crown Metal Products at some point purchased the steam air pump business from Westinghouse Air Brake. This at least involved the stock of spare parts and I believe the patterns, etc. to make new parts and complete pumps.
In time, Crown sold this business to Bernie Watts (Backshop Enterprises) of Wheat Ridge, Colorado. Steam air pump parts are still available from this firm. Mr. Watts does pump rebuilds and also supplies other specialty items for steam locomotives. No known website.
There is a web page devoted to Amusement Park Trains and it has some information about Crown Metal Products. You can try this link: