Nice name,
It's such a hard one to appraise because of the very specific nature of the equipment in question.
I can't see any further than mid $xxx at the moment but that really is a ballpark so forgive me if I appear way off.
However, it could be that Sensor (who manufacture geophones) might be interested in bumping up their traffic, worth a shot I suppose!
p.s. I don't know if it would have any tm issues with Sensor??????
Best of luck
ak