If you live in the US, you can get 100 for $37 at NewEgg, RiData 4x +, and you'll notice in the customer comments people have been saying that lately they are jpnr01s, sometimes they can be Riteks R03, but you can look at the customer comments and judge for yourself the risk in getting something other then JPNR01s. Having said that, I think TDK, Sony, Fuji +s, Maid in Japan TY02s, are just as good as jpnr01s. Although someone has commented a further improvement with the U firmware and JPNR01s. Staples has Sony MIJ TY02 +s 50 for 19.95 and out of 5 cakes, at my local store, only one was Made in Japan. BB has Fuji MIJ TY02 +s for $40.
Also videohelp.com has a very good media data in which you can do research.