epitaph horror movie 1987?

hi there guys!!

i want to know if anyone of you knows where can i download or buy (if it's possible) this movie its called epitaph (not the asian movie), its also called mommy's epitaph

Tagline:

Yes Mother^×I've done my homework, cleaned my room, and buried Daddy.

Plot:

A family must keep moving from town to town because the mother is a psychotic axe murderer who keeps flipping out and murdering people.

thanks guys i hope you can help me out