Okay got some more pictures, my apologies for the misleading info, I should have done some more looking into details and preparing before I posted this thread.
I've only wire wheeled the anvil and its base, and applied some lacquer on everywhere but the face and horn for now, to preserve my progress while I wait for more information to come in through here. I'm hesitant to remove the anvil from it's 10" pipe base, as that was assembled by my late grandma's father, and may have sentimental value to my grandpa.
Thank you for all of your input, I want to do this the right way as I've decided to simply return the anvil to my grandpa, restoring the anvil for free being a Christmas gift to him. Someday I'll either inherit it, or buy it from him. Hopefully you'll take a look at the attached photos, and understand why I mistook the manufacture date to be 1823, instead of what is probably 1923.
The face is remarkably flat and smooth despite being outdoors for the better part of 50+ years, I have Bakersfield's astonishingly dry climate to thank for that. Aside from some little raised spots that appear to be leftovers from a welding or torch operation done near the anvil, which I can take a stone to and gently bring back down level with the surface or as many have mentioned, forge on it. It's in a lot better shape than I had originally made it out to be.
Thank you again for all of your valuable insight, this project has been really fun for me thus far.
Here are the pictures: