We found this at three stores including Amazon and DK Hardware Supply. 

Prices are currently typical for this product, ranging from $40 to $69, and the lowest price we've seen is $24.99.

This product is also marketed as the 

CML Hardware Entry Door Knob with Lock and Key, Keyed Different, Exterior Door Lock Sets for Front/Back Door, Round Ball Handle, Matte Black, 2 Pack at Amazon

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[2 Pack] BESTTEN Keyed Entry Door Knob, Entrance Door Lock, Keyed Different, Standard Ball, Matte Black at Amazon

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2 Pack Entry Door Knob Lockset and Single Cylinder Deadbolt Combination Set in Matte Black Finish, Keyed Alike Exterior Knob Lock and Deadbolt for Front Door and Outside Gate at Amazon

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home improvement direct 2 Pack Keyed Alike Entry Door Knobs and Single Cylinder Deadbolt Lock Combo Set Security for Entrance and Front Door with Classic Matte Black Finish at Amazon

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(2 Pack All Keyed Identical Deadbolt Door knob Single Cylinder Deadbolt Lock Combo Set, Classic Matte Black Exterior Door Knobs with Deadbolt Entrance and Front Door Lock at Amazon

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2 Pack Matte Black Door Knobs,Interior Door Knob with Lock,Coastal Style Door knob for Privacy and Bedroom (Keyed Alike Combo) at Amazon

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