I am still riding the streets looking for that lid. I'll probably end up buying a replacement. Any other options/mods?

I have one if you get to that point.  Sounds like you'll need the lock tumbler assembly too?

You can take those apart to 're-key' them to your key.

Damn, I have to rekey it too?

And Stasch, how do you always have so many parts?

How did that happen? Don't you lock them before riding?
Even then the hinge should hold it on,... or did the hinge break?
Yes, you'll have a different key for the new pocket but if you're not worried about securing them, you can remove all the sliders/tumblers from the lock barrel which will allow any key that fits to open it.

I don’t know exactly what happened. I may have left it open because I was in a hurry that morning heading to work. No lock. That lid had one of those knobs which was never very tight but seemed to work fine. The hinge has always been loose on that lid so it has a tendency to slip off easily. I had my Cell phone in the pocket!! It would’ve flown off If I hit a bump.

don't need a new key.  simply take the locking mechanism apart and rearrange the pin locations until your present key works.  fairly easy and fast to do.

Damn, I have to rekey it too?

And Stasch, how do you always have so many parts?

I have owned around 15 C10's over the years.  Some were parts bikes that I bought cheap knowing they had engine issues (fatal hydrolock, etc) - other's were restored back to sound functional condition and put back on the road to new owners.

The result of all that is a bunch of parts, many of which have gone to help keep other C10's going around the NA continent and in Europe.

I also have a non-locking knob if you don't want to re-key or worry about locking the hatch.