How complicated a part to make?
Here's my two bits. Knock it down to as few parts as you can get it to and still test the function of each of the various parts and get to know them REALLY well, and all will become clear.
But yeah, it sounds like a hand that is worn or not quite long enough. Stretching the hand by tapping along the section between the pivot and the actual hand pawl itself can be done, but is a bit of a kludge and if the part has been done before, poses the risk of breakage. It is helpful to have a cross peen stump to use, which will cause the majority of the stretching to happen in the intended direction. A small cross peen hammer is OK but harder to control where the strike actually take place, for most folks. A game of silly small dimensional changes. Go slowly, test fit often!
I figure a drill press and a few decent condition files should do it, and you can skip the drill press if you are a half decent hand with a hand drill.
A Sharpie marker to lay down a layer of ink on your donor stock, and a sewing needle or other sharp pointed scriber to scribe and outline of the part.
Then file.
Easy no?
Like as not gonna take a couple tries.
The flash way to go would be to order yourself a Jewelers saw, a couple dozen blades, and some flat stock of appropriate thickness to be able to skip having to hacksaw stock off a bar and file it to thickness.
Starrett Flat stock in smaller sizes is pretty affordable. O-1 or W-whatever (for Oil hardening or Water hardening) would work well and both are easy to heat treat at home.
Otherwise a slab of old chevy spring, or a suitable chunk of some other carbon steel should do OK, depending upon your confidence levels, persistence, and skills.
Cheers
Trev