The prices for imported bikes aren't much higher than you'd pay retail in the States, considering currency exchange rates. You may find something unique or otherwise unavailable in the States in bike shops here, but there's a big demand for American and European bike products, so, you'll see a lot of familiar stuff.
thanks! Well I just arrived back home. It's a shame that I didn't read this earlier because the museum looks good. I found one good shop in downtown osaka hoping to pick up a team nippo kit. they didn't have it.