I can buy rice at Costco in the US for $25 for 50lbs, which is equivalent to 854 yen for 5KG. A bit less than 1/4 the cost of Japanese grown rice.
replies(9):
Surprising, because while its widely available in California it seems to be a tiny minority of available rice. A search I did says it is 80% of California's crop, so presumably a lot of it is exported?
There is no "best rice" any more than there is "best pants".