The only "safety" is you. You can test for "push off" by cocking the revolver and attempting to "push" the hammer forward with your thumb. This will let you know if there is unacceptable part wear.
single action revolver example colt peacemaker
It is a dual action revolver
You take it to someone who specializes in them.
Yes their a good single action revolver
1873 was the date of the first one.
depends on the model revolver. single action just in front of trigger guard............ modern revolver bottom of butt............
about 1883
1873
1927
1895
1962
10-100 usd