I recently got a Puma 92 lever action in .357 and I think there may be a pin missing in the receiver.  There is an open hole above the loading gate at about its 1 o'clock position.  it is the farthest right and upper most hole from the other screws/pins on the side of the receiver.  The action functions and fires fine with no problems from about 200 rounds through it so far.  Is this hole supposed to be there or has something in the action come out??

That hole is normal. On the other side of the receiver you'll find a plug screw directly opposite the hole. During disassembly, the plug screw is removed then a drift is pushed through the hole you see and the pin that connects the lever to the bolt is pushed out through the unplugged hole.

For me that pin was a pain to get out. I was worried I was going to bung something up and wasn't tapping the thing hard enough. I gave it one more whack and it finally came loose. Be careful when removing or putting it back in, try not to mess up the threads of the plug screw hole.

ETA, there are instructions around a couple different forums for taking the M92 down, I would suggest that you follow them when doing so or you may become frustrated. Some folks don't bother and just use gun scrubber and compressed air after removing the buttstock to clean the action without taking it down.

It's been a long time since I've torn one down, but iirc, jiggling the lever to get it lined up was crucial.
My current 1892 (.32WCF) was made in 1914, and I have no real desire to fool with it. It's just too easy to scar the screw heads, even with good screwdrivers.

Thats a beautiful rifle.

Original Tang sight or new? Been thinking of getting a Marbles for mine.

ETA: Is that a fiber optic front sight?

The original sights were missing, and it came with the tang sight and the folding rear sight. I had to replace the front sight because it was damaged, and the fiber optic was the first sight I found in my parts box. I like it though.
The tang sight isn't visibly marked except for a "2" stamped on it but it is adjustable for windage and elevation; I doubt it's very old, but I like aperture sights and it's right there about two inches from my eye.