All - I wanted to update this thread and tell everyone that I think I've found my seat. It is awesome. I feel like a kid on Christmas day (the best Christmas ever!). I will post some pictures later. It appears to be NOS but still has a couple of issues. I was hesitant on most seats posted here because they didn't have Troxel on the little flap (as I know almost all Troxel seats between 1915 and 1920 that I've ever seen have) or they appeared to be a later seat than 1919 (I based what I thought a 1919 seat would look like on what other verified seats of that time frame looked like). I really feel that what most people have posted on this thread are late 20s to late 30s. Awesome and amazing seats, I loved seeing them and would LOVE to own them - but not quite what I was looking for. This is the first juvenile seat I have ever seen like this. It also clearly has Troxel stamped on the flaps, and Troxel didn't exactly make a bunch of different juvenile models during that time. I'm 99% sure this the same seat that was on this bike in 1919 when a happy little boy rode it the for the first time on Christmas morning.
Now there is a couple issues with this little seat, even though I don't think it was ever used. It is very dirty and needs to be cleaned and hopefully oiled somehow. And the carriage is pretty rusty. It looks like it probably sat in a pile of seats or other parts in a warehouse or outbuilding for quite a while. Something was pressing against the front of the frame and pushed it over to the side into one of the flaps. I REALLY do not want to attempt to push it back myself (or unscrew it to move it back). I am hoping to find someone who is an expert on these seats who can possibly take it apart for me, clean it up, get the leather treated somehow and get the carriage looking good, but not new. If you know anyone, please give me their name or direct them to me. I would really appreciate it.
Hopefully this thread will serve as a place for those in the future looking for an extremely rare and hard to find juvenile seat to come "shopping". I was shocked how many seats are actually out there (if someone is willing to spend some money! haha).
EDIT: Another thing about this seat that lead me to believe it is much older than the seats posted in this thread is that it is made of wood and has actual leather stitched to the bottom. This is the first one I have seen like that. Maybe some of you have seen one.