Do I have a burnt/burned valve?

Why change the points??? They won't cause a single cylinder to misfire. Just make sure the dwell is in spec and leave them alone. As for plugs, if they are old, replace them. Yes, a bad plug can cause a misfire but so can lots of things. How old are the wires?

A couple of thoughts from the video:

First, it actually sounds OK. I don't hear a major misfire, but it's tough to tell. I'm betting that your dual exhaust doesn't have an "H pipe" or crossover. This will cause the exhaust to "pulse" because of the uneven firing order. Remember that the engine fires left-right-right-left-right-left-left-right.

Second, the (warm) video does show a little about the health of your heads. Your valve guides are passing oil big time. When you rev, lift off and hit the gas again there is a pretty good puff of blue smoke. (there's also a puff of black smoke when you hit the gas, indicating that you are way rich, have too much pump shot, or both). I bet it blows a small cloud when you first fire it up in the morning. If these heads have some miles on them, that's typical, but loose guides will shorten valve seat life. If the heads have never been off the engine, then I wouldn't be surprised if they were getting tired. If the original timing chain and cam sprocket are in the engine they're on borrowed time and you will be doing a valve job to repair the damage.

As said before, you must DO A COMPRESSION TEST!!! There is no better way to diagnose the overall health of an engine. Just throwing parts at it and guessing is a waste of time and money. You can't tune an engine with uneven compression and internal vacuum leaks!

If this is the original engine, it is showing it's age. If you determine that you need to do a valve job, using a set of "302" casting as your cores makes a lot of sense. You can keep running what you have and them swap on the rebuilt heads. If you are planning to build another engine, why put any money into this one?