Yeah I know... I was just soooooo excited when I found that documentation but Eric reminded me there is a lot of variation by area, etc..
So yes mine could be original, or later doors that were cut to fit. Eric's could be original, or salvage even older than his house. I guess all of us can only Guess. (we need some DIY carbon dating kits

)
Jeff-
I don't know about sources that make reproductions. Actually if you find one let me know .... A few of the rooms in my house that were redone had the trim replaced/covered with modern off the shelf stuff. I could see someday undoing that as I put all the old doors back.
Don
I'm envious of your front door. The one I'm replacing is probably only 30 years old or so and already toast. In my garage I have an older batten door but it doesn't look original either. Its got reproduction strap hinges and doesn't look weathertight at all... big gaps in the boards. might have been used as a storm door ?
Thank fully the PO's asked if I wanted them to throw out all the old doors in the garage before closing (NO!!). In the house we have 3 of the original 4 panel jobs, and a bunch of stained 6 panel home center replacement doors. I can even see where they put new trim over the old casings to make the jambs deeper for the modern 1 3/8 doors. But out in the garage Ive got a 3 or 4 more 4 panel jobs, plus a bunch of horizontal panel doors that look like late Victorian/early craftsman style. Interesting colors too; some white, one is yellow, one deep green, another is PINK. The 4 panel doors all have evidence of both thumb-latches and mortised locks. No rim lock boxes that I can see. They all have cutouts for mortise butt hinges but interestingly none have marks of filled nail holes from H or strap hinges.
Of course when somebody redid the upstairs they tried to make it look old with strap hinges on every door. Even the closets.
Anyway I'm rambling on. Bottom line is the interior is a mutt of 3-4 different periods and my goal over the next few years is to try and redo it in a more unified theme throughout...
Thanks again for all the compliments and suggestions. All the feedback is very appreciated.
-Jeremy