Random Frame Time Expression - Stop Motion

Hi all.

I'm working in stop-motion and looking for an Expression.
I have been working in After Effects until now, but moving to DaVinci Resolve (LOVING it!).
What I am looking is an Expression that lets me play back a random frame from a video, sequence or Comp.
It is used to make drawings visually more interesting and give them a more natural feel, than a repetitive loop will.
So instead of playing back frame: 001, 002, 003....
It would play bach: 009, 025, 006, 012...
I hope I'm making sense.

This is what I would use in After Effects:
fr = 12; // frame rate;
numFrames = 8;
seedRandom(index,true);
seg = Math.floor(time*fr);
f = Math.floor(random(numFrames));
for (i = 0; i < seg; i++)
f = (f + Math.floor(random(1,numFrames)))%numFrames;
framesToTime(f);

Use a time stretcher and modify the source with a shake modifier with its min max values set to the range to choose from.