Wisps in NK are always good for cash.

Lightstones sell to the Gypsies for 1pp+ and if you give the Greater
Lightstones to Mrysila (?) you get a research book you can sell back to her
for about 9pp (and some experience as well).

Not sure how safe a place to hunt NK is at level 12 though - probably OK if
the Griffawns don't agro on you.