Yours might be in the "Recovery Files" folder that comes with the latest version of hddhackr, did you look there? You didn't specify your exact model, but these are the ones in that folder:
WD800BEVS-00VAT0 (11-07-2008).BIN
WD800BEVS-07RST0 (01-15-2008).BIN
I realize this is long shot, but I'm looking for an undo.bin for:
Western Digital WD1600BEVS - 60RST0
Date: 26 FEB 2008
Haven't been able to find it in any of the WD packs. Thanks!
Edit: I found a dump of the undo.bin on pastebin, but the encoding looks different than the other undo.bin...