Mostly conservative. However the extent varies across socio-evonomic demographics within the Sinhalese community. Out of the basis set that hold conservative political views, ideas ranges from mildly free market libertarian to extreme authoritative (sometimes borderline fascist) governing.
Having said this, it should be added that we Sinhalese do not really think in terms of a particular right-left demarcation. Historically speaking such classifications are loosely, if at all, absorbed by our culture- a good example being the equivocal nature of “socialist democratic republic” mess.