CJackson said:
How much do the Japanese special collections run for on eBay?
Quite high if I remember correctly. They're not as common as the other LD sets, so I've seen them sell from $50-$100 each. You may wish to check prices on lddb.com.
However, a cheaper alternative you may want to consider, if you just want no motion smearing, are the Special Widescreen Edition laserdiscs. They're slightly lower quality but have no Japanese subtitles. Also, many pressings of ANH have an aspect ratio error.
The cheapest way to get the Japanese Special Collection versions would be to get one of the preservations made here. Arnie.d.'s V8, an excellent transfer of the JSC version of A New Hope, is available on both Demonoid and the a.b.starwars. As for Empire and Jedi, you can get Dark Jedi and Segaflip's old preservation of them on a.b.starwars.