CXS/IPA question

What would be the approximant equivalent of [1] (barred-i)? I'm considering
M\, though technically that's velar.

The problem arises in my &%*#& Gwr sound changes: some *bdg > BDG, which
later > approximants **w,j and __? )-- these form diphthongs with preceding
V-- Vw, Vj and V@.  In modern Gwr phonology, @ is merely an allophone of /1/

I've been using h\, not quite satisfactory, though in the distinctive
features I'm using it's possible to contort it into @, it's just not very
elegant.........:-(((