"The low frequency contrast between /s/ and /t/ is found mainly in words borrowed from English and Hiri Motu. ... The few contrasts between /v/ and /w/ are found only in words borrowed from English."
(In native vocabulary, w t > v s / _e _i.)
Allophonic rules
β >
v / (non-canonical form - i.e. alternate representation of the phoneme)
ɾ >
l / (non-canonical form - i.e. alternate representation of the phoneme)