I bought the chair. I couldn't do too badly for $45! For some reason, the photos I took yesterday with my cell phone are huge and I'm unable to reduce or send them, so I will retake photos and post them shortly.
One of the stretchers on the legs is most definitely a replacement from another chair and does not match at all. There are remnants of old red paint and old varnish. So yes, this chair has old repairs, but is in sturdy and very usable condition. There may be other replacement parts as well, but everything looks like it was done long in the past and I'm not seeing any recent meddling with it, so for my purposes, its all good.
This chair is a little too short in the seat height to work with the very tall 1850s plantation desk that I had planned to pair it with, but it looks fantastic with the 1810s Virginia great wheel (large spinning wheel) I have and will be using for historic reenactments. That super-tall stick back has got a really eye-catching look to it and the whole chair has a very old-timey, homemade look to it.
Nothing is known of it's history. I purchased it locally here in Northeast Tennessee and the seller got it in the purchase of a storage unit she is flipping. I suspect the woods will turn out to be local hardwoods, I have a friend that can help me ID them when I see him again. I'm going to guess hickory and chestnut.