This is a list of shops who sell red/cyan 3D glasses. If you know of any, please add them in a reply. I'm also adding the date they were seen so there is some idea of how current the information is.
1 2 3 World (3 June 2012) in shop M110 at Milford Shopping Centre Auckland (09-489-1230)
The glasses they sell have big frames, allowing you to view 3D anaglyph content without seeing the frames of the glasses.
Price: $6.00 / each