A couple of suggestions.
X Japan have been around for a while, and are quite big. I'm surprised they're not here. Although mainly Power Metal, they have some very Prog stuff, the Dahlia album, and the 29 minute Art Of Life.
http://www.xjapanmusic.com/audio/
^ music and stuff there, more progressive songs are "Art Of Life", "Rusty Nail", "Dahlia"
Blue Gillespie are a Heavy Prog, sort of Doom Metal band, who do have some very progressive elements, but I think it's up to some experts to decide on their inclusion.
http://www.bluegillespie.co.uk/static/Music
Decortica are a band from New Zealand, and NZ hasn't been very well represented on PA, so I thought I'd suggest them. They have some very progressive elements, but once again, I'll leave someone else to judge that.
http://www.facebook.com/decortica?sk=app_178091127385