is it possible to rebuild a door latch

After nearly 300K miles, the front and tailgate latches seem to be wearing out. Replacements are more than $150 each. So is it possible to disassemble them and replace or repair internal parts? My first look at the tailgate latch tells me that getting in will be tough - the assembly pins are pressed at the ends, and it looks like I would have to grind them off.

Or am I missing something?

 

Pulling some off one from a junkyard not an option for you?

 

Yes, but if they are worn also, I though rebuilding some of the components might be an option. I used my welder to replace worn-out metal in the clutch pedal linkage (to eliminate the slop), and I thought maybe to do the same here.