Thats a hard question. One thing working in your favor is that the damage to spokes from the DeR will be nearer their middle, whereas the place the spokes break is closer to their ends. And so, even some were nicked up, it will not necessarily make the spokes substantially weaker.
However, if this was me and I did not know the seller, I would only be interested in the wheels for a low-ball amount. Any used wheel is a gamble, in fact. And these more than usual. If the deal is truly great (if the wheel failed, could you still smile and shrug it off?), then its not a crazy idea.
jim
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Cross Check Nexus7, IRO Mark V, Trek 620 Nexus7, Karate Monkey half fat, IRO Model 19 fixed, Amp Research B3, Surly 1x1 half fat fixed, and more...
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SB forever