Methinks that they will add it on paper somewhere else and claim that you agreed to it and that the contract meets government guidelines. They could be tacking on the cost of the apartment and the insurance premium, their share that is, as the sum total that will bring this up to specs. 167,000 in Sendai City won't buy WalMart Toffy for tea. That is not good. 250,000 is minimum lifestyle.
Rice is over the top.
Unless you are planning on losing a lot of weight, the salary they are proposing to pay you will be a serious problem. Yamanashi in 1987-88 and it was not nearly enough. If you send money home they really gouge you for conversion and then again for sending it. Unless you are really in dire straits, don't take this job. Which buy the way, is often the way it is.