Thanks for the pics. I see a couple of interesting things. I have figured out with your addition pictures that it is a small frame H&R Premier late model. I have one in 22LR that looks a lot like yours, but not in as good of shape (see picks below).
First, is this pistols set up to be a double action only pistol, meaning that the hammer doesn't lock back? I'm asking because I just noticed that there doesn't seem to be a sear that is supposed to protrude out of the inside rear portion of the trigger guard behind the trigger. It looks like that is missing in your original pictures. With it missing then it makes the pistol a double action only and the hammer cannot stay cocked.
I've included a picture of some H&R pistols I have and the 22 Premier I own is in the nickel one in the middle. See how the sear protrudes out behind the trigger? Yours seems to be missing, or the spring is broken, I can't tell which.
Second, this is the style of pistol that has the spring steel cylinder stop. I can tell by the 2 pictures you sent me of the overhead view of the cylinder stop on the trigger. If you look in front of of the cylinder stop on the flat part part of the frame right by were the barrel pivot connects, you will see what look like a small pin in the flat portion straight in line with the cylinder stop. That is actually a screw that is screwed in from the underside and can be seen when the trigger guard is removed. That screw holds in the steel spring cylinder stop. I've added a link to the picture of the cylinder stop you need from the Numerich Gun Parts website. The screw hold the steel cylinder stop in place by screwing through that hole. These are a pretty common part that is broken. This cylinder stop is designed to stop the pistol from freewheeling. I replaced it on my 22 Premier and sure enough, it no longer freewheels. The cylinder stop built onto the trigger is to lock up the cylinder when it is cocked, along with the hand, which both seem to be doing.
Cylinder Stop | Gun Parts Corp.
I really can't tell if the hammer I have will work or not unless you remove it from so I can see the teeth. H&R did offer bobbed hammers as an option, which would make the pistols a Police Premier. But looking at the hammer closer, it doesn't look quite right.
So, now you have three things to fix on this pistol to make it work properly.
1. The cylinder stop. $7.00
2. The hammer (if I have the right one) $25.00
3. The sear and the sear spring. $12.00
Doing some adding up on those basic prices and your at $44.00, if all these parts can be found, which is almost what the pistol is worth.
I'm now thinking along the lines with what Old Cop said earlier, I think your friend should give it to you.
I hope all this information has been helpful.