Created by myself based on modifications of the vector outlines generated by the following PostScript source code:

%!
300 396 translate 1 setlinecap 1 setlinejoin 10 setlinewidth
/turn1 245.4 def/turn2 -76.1761281 def/turn3 185.3 def/turn4
-35.0968012 def 0 0 53 turn3 turn4 arcn
33 turn4 cos mul 33 turn4 sin mul 20 turn4 turn4 180 add arcn
0 0 13 turn4 180 arc 
113 turn2 cos mul 113 turn2 sin mul 40 180 turn2 arc
0 0 153 turn2 turn1 arc
133 turn1 cos mul 133 turn1 sin mul 20 turn1 turn1 180 add arc
0 0 113 turn1 turn2 arcn stroke 0 0 133 turn1 turn2 arcn
113 turn2 cos mul 113 turn2 sin mul 20 turn2 turn2 180 sub arcn
0 0 93 turn2 180 arc -93 -40.3167 -51.3623 -73 0 -73 curveto 
0 0 73 -90 turn3 arc
53 turn3 cos mul 53 turn3 sin mul 20 turn3 turn3 180 add arc
0 0 33 turn3 turn4 arcn stroke showpage
%EOF