In my (limited) experience, it doesn't look bad. No way of knowing the true condition of soft goods (hoses, mouthpiece, diaphragm) without having it in hand, but the outside condition looks promising. I haven't seen new 2 stage diaphragms available, so I would budget for an HPR second stage and new diaphragm from VDH, and new hoses/mouthpiece from your choice of supplier. So anticipate around $150 to $200 ish, and then count anything else as a bonus. I have one DAAM that I put a cyclone 1st, HPR second, and band clamp into ($150 in parts, excluding the hose loop), and another that I resurfaced the factory 1st stage seat, and it had a good diaphragm in it... so it cost me about $10 (exclusive of hose loop). Just the roll of the dice with what you will find inside.
So in short, to me it looks like either an OK or good deal, depending on condition of soft goods.
Respectfully,
James