Nail Gun Massacre is the perfect Rifftrax movie. Made during the slasher era when everyone was throwing a new hardware-using killer onto VHS, it's a horrible movie that has one thing that really makes it perfect.

All throughout the movie, the killer is very clearly male. Big, built, but wearing a leather jacket and motorcycle helmet while nail gunning people.

In the end, it's revealed that the killer is a woman. A very small, petite woman. Magically, she apparently grew five sizes every time she went a'killin. It's so hilariously awful as a reveal.

To add to this you get terrible framing/directing moments.

An actor falls off a tall conveyor machine in a quarry supposedly a hundred feet in the air...landing on the STILL VISIBLE pile of sand immediately below it.

A little girl goes to pet a wolf at a zoo. Shown in the inset petting the wolf, a huge, rugged male hand.

This movie is more gender-confused than Caitlyn Jenner making out with Pat from Saturday Night Live.

I also don't think it currently has distro. I'm not even sure it's been on DVD yet, definitely not Blu, so it might be a cheap pickup for you.