You can try an Onda VX585 from HouseofDap.com.
It has a 4.3" screen player and under the $100 mark you were looking at. Plus they sponsored this player as a prize on this site.
Take a look here:
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http://www.houseofdap.com/onda-vx585-hd-player-1080i-720p-hdmi-out-4-3-lcd-8gb.html]
Here is the review from the member who won the player:
http://mympx.org/forum/reviews/44994-review-onda-vx585hd-houseofdap-com.html
There are also players from MP4Nation.net as well which you may want to consider. Both are pretty good and reliable sellers as well. Well, there is always a risk when you're ordering online and not from a local store, but it tends to be cheaper. So it's just a matter of whether you want to pay the extra for the 'comfort' of dealing with a local retailer.
Hope that helps.