I think you're talking about the 95 Eclipse knob. Cant find it on ebay though, but I know they(used to) sell all the time there.
http://forum.miata.net/vb/showthread.php?t=372416
http://forum.miata.net/vb/showthread.php?t=316832
I looked up that one a few years ago, decided I liked the mitsubishi EVO mini baseball knob better.
http://www.3sx.com/store/comersus_vi...dProduct=27501
These go for super cheap on ebay as well, but I can't find any now.
My wife bought me this one for christmas one year, 2010 Ralliart Lancer knob and I love love love it. Problem is its over twice as expensive, it's super light, and when I got it I realized it's from a manumatic transmission and it's only partially threaded. I had to drill and tap the threads so it would go all the way down. After all that, I love it, haha.
http://www.ebay.com/itm/2010-2011-MI...66d79a&vxp=mtr
Good luck looking for them, I can't seem to find the first two at their normal $20 - $40 prices, but i've seen tons of them sell for that on ebay so I know they can be had.