Dec. 7 (Bloomberg) -- North Korean rice prices have more than doubled since the government revalued the currency last week, a South Korean aid group said. North Korea’s regime ordered citizens to exchange 1,000- won notes for a new 10-won bill, Yonhap News Agency reported on Dec. 1. One kilogram (2.2 pounds) of rice cost 50 won as of Dec. 5, compared with 16 won to 17 won on Dec. 2, Buddhist aid group Good Friends, which obtains information through contacts within North Korea, said in its newsletter today.