Usually, the cam bearing failures are pretty much confined to the lower half (the portion of the bearing that resides in the head).  That is the part of the bearing that carries all the load.  If a failure gets bad enough, aluminum will liquify and get dragged through the top half (the portion of the bearing that resides in the head cover).  If you have a problem with this left-hand bearing, it will be evident once you get the cam out.

I think that you should immediately try to remove your right-rear cylinder stud.  The complexion of your project will change dramatically if you can't get that stud out, so you should attack that immediately.  Do you have your stud removal tool ready?

I agree that your rocker pads have some scoring.  I resurfaced one used set of new-style rockers (the ones with brazed pads) using wet & dry sandpaper on a surface plate.  It is not something an inexperienced wrench turner should attempt.  You need a perfectly flat plate and an experienced feel in order to maintain parallelism and the correct radius.  I think we need to see those cam lobes to see what the pads have been running on.

Regarding those sealing washers, when they have been in service for a long time, they tend to get stuck to the underside of the flange on the hex head.  When that occurs, it can look as if there is no washer.  Look very close; make sure they aren't stuck on the flange.  If in fact the washers are missing, you need to get some OEM washers.  For sure you want an OEM washer for the one bolt that can't be removed without pulling the head cover back off.

This picture shows one of the lock tabs (yellow arrow).  Also note the green lines that show how the timing marks on the cam line up with the head surface.  The timing marks must look like this when the piston is at TDC.

This is the thrust ring.  You want this in place when you bend the lock tabs on the sprocket bolts.

The thrust ring simply rolls out of the groove, like this.

When you take the pivot bolt out, be careful not to lose the sealing washer.  The washer has a tendency to stick to the head.  See the washer on the pivot bolt.

Now that you have an idea of what to do, lets go through steps.

-Bend back the lock tabs on the cam sprocket bolts.
-Break loose the cam sprocket bolts.
-Remove the thrust ring.
-Remove the can sprocket bolts.
-Shift the cam to the left and pull the cam sprocket off it's fit (watch the drive pin, don't lose it).
-Lift the cam chain off the sprocket.
-Juggle the cam out of the sprocket and chain and head (frustrating).
-Remove the sprocket and tie off the cam chain with wire or carefully lower it into the primary case.
-Remove the rear chain guide pivot bolt.
-Pull the rear chain guide out through the primary case.
-Remove the right-rear cylinder stud and the left-rear cylinder stud.

You are ready to start cylinder head removal.