Tube replacement for Yaquin MC-10L

Can anyone be of assistance? Tube newbie here!
I've got a Yaquin MC-10L integrated amp I bought from a guy. He told me that the tubes are quite likely ready for replacing. So, it seems I need to get 4 EL34 tubes and 4 6H1N. Does anyone know if I have to get "matched tubes"? I'm not quite certain what that even means...