I sometimes use a .066 for the sixth and then the lowest 5 (6th to 2nd) from a light set (EJ16) or medium set (EJ17) of D'Addario phosphor-bronze for the rest. Got my 66s from www.juststrings.com who also sent me a .070 and a .080 which I found too heavy for the scale length of 27". Currently it's strung with EJ18 heavy guage (14-59) and only tuned down to C which seems to suit the instrument, and it's easier putting together string sets. I'm almost out of 66s, but they're easily got by ordering online from one of the string suppliers.

Give me a minute and I'll find the address of another supplier.

Peace, Mooh.