try "Multi-Pastel Chalk Pencils" from General Pencil Co in white and light grey
Also the ceramic mechanical pencil (Fons and Porter, Sewline, Collins) in white
A slection of colors from Bohin - but in white
I recommend avoiding colors as some have lots of color pigment in them and difficult to come out.
Everyone has their favorite and I don't believe there is one "best" markeer because often what works for one person doesn't work for another.