A: please google for part number D214-2-11 to get a list of resellers offering that part
A: I do not know. Westbrass makes a standard kitchen sink drain. Sometimes Kohler uses something different than the standard parts for their fixtures and looking at that number on the interweb produced no results.
A: Item Number is D214-2-62 - for Matte Black Finish. It is available online.
A: These are kitchen sink basket strainers designed to fit into 3-1/2 in. openings with an outside diameter of 4-3/8 in. They will not fit in square drains, only round. If your double bowl sink has round drains they will fit. We do recommend treating them with Turtle Wax or Maguire's automotive wax to help protect the finnish.