Lower (smaller) DISA-$120 (good working condition- see video for tightness. Slight gasket wear, but should still seal fine)
Upper (larger) DISA- $75 (This appears to be fairly loose and I would guess it needs to be rebuilt or replaced. GAS will be offering the rebuild service soon for $150. This would be good to send out for rebuild to have less downtime. Otherwise you can find new ones for $120 or so.
Lower DISA video: as you can see, its nice and tight still.
https://dl.dropboxusercontent.com/u/...211_190231.mp4
Upper DISA video: clearly there is some play, unsure of functional condition.
https://dl.dropboxusercontent.com/u/...211_190337.mp4