One modestly priced eyepiece set which is good quality is the Sterling Plossl set:
http://www.ebay.com.au/itm/STERLING-...item58936b34e2
I've compared the 25mm to a recent vintage 25mm Televue plossl and contrast and transmission looked the same on deep sky targets. The 4 & 6mm Sterlings have short eye relief and really need a driven scope to use comfortably.
Ultimately though I'd say that a couple of widefield eyepieces would be better for your dob - perhaps something from the Explore Scientific 82 degree or 68 degree lines.