You have a couple options.
1)list it for sale in our classifieds and see if you can recover most of your money. Then buy the correct stock.
2)Send it back and exchange it for the correct one.
3)Re-drill the front action screw hole in the correct location and bed in a front pillar. The correct location uses about half of the existing hole, so it is kind of hard to do unless you use a drill press and clamp it down.
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