I cannot think of any simple solution. So here it goes :
\version "2.18"
\relative c' {
%% Stem defs to be set manually;
\once\override Stem.Y-offset = #-4
\once\override Stem.length = #4.5
\once\stemDown
<c
\tweak NoteHead.stencil #(lambda (grob)
(grob-interpret-markup grob #{
\markup
\center-column {
%% Change to s0 or s2 as appropriated:
\musicglyph #"noteheads.s1"
\path #0.25 #'((moveto 0 2.2)
;; Change the Y coordonate as needed:
(lineto 0 .4))
} #}))
c'>2
%% defaulft stem length:
\once\stemDown c
\once\override Stem.Y-offset = #3.5
\once\override Stem.length = #5.5
<c
\tweak NoteHead.stencil #(lambda (grob)
(grob-interpret-markup grob #{
\markup
\center-column {
%% Change to s0 or s2 as appropriated:
\musicglyph #"noteheads.s1"
\path #0.25 #'((moveto 0 2.2)
;; Change the Y coordonate as needed:
(lineto 0 .4))
} #}))
c'>
%% defaulft stem length:
\once\stemUp c'
}
Cheers,
Pierre