I just did a search on Ebay and note there are a number of Dell Venue 8 Pro tablets that have recently sold in the neighborhood of $100. I have had one of these for the last four years, and it's been great. I suspect it would be similar to your Asus. Bad news, though, my USB port is on the way out, too. I have only one mini USB cable that will charge it, and my mini USB to USB adapter no longer works. That said, it is still going and I consider four years to be a pretty impressive life cycle for a tablet that was less than $300 to begin with and has led a pretty tough life.
There are also a few Vivotab 8s that sold recently on Ebay. They appear to be going for a little more than the Dells, but many still less than $180.
I think the Dell and Asus were really the top 8 inch tablets of their time. Maybe you're thinking you want to go with something else, though, a 10 incher or similar. I guess that would require some more hunting around.