It is necessary to include a tlv of 0x1421 in the submit_sm with a value of 0x031.
0x1422, 0x1423 0x1402 will be returned with strings containing the price, remaining balance and mcc/mnc.
ie, send a 0x1421 and get back a 0x1422 / 0x1423 and 0x1402 (mcc/mnc)