Dac problem

Can anyone help me with a J-fet problem? I need to replace some marked K147 and J72. I assume these are 2SK147 and 2SJ72, but I not been able to locate them in South Africa. These are located in the output stage of my DAC. I believe 2SK170 and 2SJ74 might do, and I have located some 2SK170's locally, but they can't tell me what make they are, nor can they provide me with matched pairs, nor can they supply 2SJ74's. Can anyone suggest other high quality pairs that I might be able to use? I have no idea what parameters I should be looking for.