Wood filler and seal coat product suggestions for black korina / mahogany

[Raise-a-Glass]

I have Minwax wipe on poly that I like and look to finish with that.  Looking for suggestions on grain filler (black) and sealer products that would work with that top coat.  Thanks. 

Here is a pic of what I have.  Since the neck and body are different shades, I was looking to use black filler to tie them together.  May do a black to clear burst by hand, but most likely chicken out.