The ornamental design for a housingwindow for a medical injector, as shown and described.
FIG. 1 is a perspective view of the housing viewed from the front and left of and above the medical injector;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a right side elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken line showing is for the purpose of illustrating portions of the article and forms no part of the claimed design. The broken line which defines the bounds of the claimed invention forms no part of the claimed design.