I think different people are using different names for different parts.
Post 1: hand and the boolt broke yetsterday.
Post 2: might as well get one or two trigger/cylinder stop springs
Innyhoo, hand spring is far away from the bolt. THAT is a trigger connected part.
Item 2: That hairpin IS the trigger/bolt spring.
THAT part, I would suggest you buy the ones made for the 1873 model. They are still made today. Buy REAL COLT springs. They may be made by Pietta or Uberti but they are SOLD by COLT, by god, and you will pay COLT price.
Then, too, you MIGHT buy the wire model. Seems they work the same but last forever, like Ruger springs do.
Cheers,
George