If I needed parts, especially springs or a hammer-mounted firing pin, is there any place to get them.

It's a model 1905 4th change Hand Ejector in .38 Sp. made sometime in the 1930s. The extensive wear pattern on the finish has "cop gun" written all over it. It works. The timing notches on the cylinder have some burring.

Thanks.

Might try these places

https://www.gunpartscorp.com/

https://www.gunsprings.com/

https://jackfirstinc.com/

Might watch GB for their gun parts kits; this one is up right now. https://www.gunbroker.com/item/1065797640