You can easily make any pin from drill bits. Just check the size, cut it off to length with a dremel wheel. Peen down one end of the pin to hold it. Polish the ends, and use Birchwood Casey's perma blue and a qtip to blue them.
Trigger return springs are easy to manufacture also. Use a "flexible" hacksaw blade. Cut it to length using the existing hole as the hole that's needed. Bend the piece to fit, and trim down to shape with the dremel grinding wheel. As soon as you get it to fit, heat the piece to dull cherry red color, and then plunge it into cold automotive oil.
I am shooting IJs and H&R revolvers with home-made parts I made a long time ago. I guess I'm just an old cheapskate!