The Undermine Journal puts it in the 500g range off of the AH but only costing about half that in mats.
But then I went to femaledwarf.com and plugged things in. In the hyper unrealistic theoretical world, I'd be doing 27,164 dps with this instead of the X-Ray scope. How much better is it? Less than 23 extra dps. Yes, less than one-tenth of one percent better.
That said, it's occasionally throwing small critters so it's gotta be great.
PS: My two-week hiatus here was due to a well-deserved vacation touring England and Wales. It was "well good" as I heard up in the Yorkshire a few times.
PPS: I got the scope and the squeal sound effect is a bit more noteworthy than the "x-ray" effect. TBH, I don't even know if the "x-ray" effect has any effect other than the buff icon.