The "old Mrs. Compson" who gave Old Het the "purple toque" that she has worn for "fifty years" is the wife of General Compson (242). She is only mentioned in The Town.
Spilmer's name is mentioned when Hait tells I.O. Snopes where the mule she bought can be found: "in the ravine ditch behind Mr Spilmer's house" (264). This is his only appearance in the novel.