I'd take a look at what's in your eyepiece box to see if there's a gap and which of these best fits in - you're spoiled for choices:
LVW 22, Panoptic 19, 22 or 27, or the ES 68-degree series 20, 24, 28 or 34mm.
Your scope could take a longer f.l. eyepiece, or wider too... if you subscribe to the "mine's bigger than yours" principle you could get one of these babies
http://www.youtube.com/watch?v=nnjlmxHQfmw