The Fluke 15b and 17b you see on ebay mainly seem to be available from asian sellers because they represent Fluke's brief experiment with outsourced manufacturing.
They are genuine Fluke in the sense that their design was specified by Fluke and they were built to Fluke quality standards.
They are actually made by Extech, or rather the company behind Extech, who also makes all of the Craftsman brand meters, including the 81437 which is a 17b in red plastic with some buttons missing.
I've seen the insides of my 81437 and the insides of a completely different extech-branded meter, and they had the same processor core but the 81437 was otherwise built with much better quality parts.
fwiw Wavetek/Meterman is 100% as good as Fluke at a fraction of the (ebay, gently used) price. IMHO.