They don't really make any newer cards that are that slow, until you get down to the $50-75 price point. I can guarantee you that if you're still happy with an X850 Pro, you'll love an X1950 Pro, for ~$100.
edit: BTW, the new 2400XT is about as fast as your X850 Pro (although it's probably slightly slower), if you want to look up some video card comparisons, like
this one.