As far as I know the left head is a custom.The right one appears in 8 sets: http://www.bricklink.com/catalogItemIn.asp?P=3626bpb022&in=SThe hair comes in three colors and appears in 11 sets: http://www.bricklink.com/catalogItemIn.asp?P=43751&in=S
This thread should be in the master part indentification thread though.My thoughts exactly - YC :o)
Does the Spider Droid from the SW Advent Calendar have a catalog numer? I see the Mouse droid is the same from other sets and has one but can't find one for the Spider Droid.
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