I claim the ornamental design for a handheld canister vacuum cleaner motor assembly, as shown and described.
FIG. 1 is a top, front and left-side perspective view of a handheld canister vacuum cleaner motor assembly showing my new design;
FIG. 2 is a rear view thereof;
FIG. 3 is a left side elevation view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a right side elevation view thereof;
FIG. 6 is a front elevation view thereof;
FIG. 7 is a bottom plan view thereof;
FIG. 8 is a reduced top, front and left-side perspective view thereof; and,
FIG. 9 is a reduced right side elevation view thereof.
The portion of the canister and vacuuming attachment shown in broken lines in FIGS. 8 and 9 are for illustrative purposes only and form no part of the claimed design.