Good pictures and information JB. Let's look at some of the things we now know.
First, these came back as root suckers. If the original pear tree at that location was a grafted pear (which is highly likely) what you now have is not related in any way to the grafted variety. It is a clone of the rootstock. The rootstock could have been one of the common ones like nurseries use (such as the various OHxF choices) or some nurseries just grow seedling pears and graft to those. Every seedling pear is a new variety that has attributes of its own, just like ever person is a new person.................
Based on the above paragraph, it could very well be either of those. I have never studied what kind of fruit any of the common pear rootstocks produce, but maybe someone else here has studied that and can chime in.
If it was grafted to a seedling, you have the only one of those pears in the world..............
Another possibility is that the original pear was started by a cutting or root sucker of a named variety. That is possible but probably less likely. But for discussion sake, lets assume it was. What we now know is that your pear is not a late dropping variety like Kieffer, Warren, etc. By the looks we can also rule out many of the early varieties that don't look similar. Century Farm has a picture of an early pear called Plumblee on their web site that looks a lot like your pear. Unfortunately, I don't grow that pear so can't tell you anything about its attributes.
Your pear ripens about the same time as Ayers, but we can easily see from your pictures that it isn't that one. Your pear looks a little more like Moonglow, but there is just enough visible difference that we can eliminate that one too.
For the Asian versus European discussion, that can be really cloudy, because the two types of pears have been known to cross pollinate and produce pears with attributes of both parents. Kieffer is thought to be one such pear, although I'm not sure anyone could actually prove that.
One thing I find interesting is that I had a pear to come back from a rootstock and now produces early pears
almost exactly to your description. The ripen real early, hang on the tree until they rot, the flesh is like you describe, and my pears look very similar to yours. This leads me to believe that you and I could both have a pear from the same rootstock.
I probably haven't helped you much, but I did maybe help to eliminate some possibilities. Pic of my rootstock pear is shown below:
