I get it now, I was too excited. So it's Rifles for Wands then, since Wands represent Fire.
This is a great project. Thanks for reviving it, Lee!

I'm looking at my "Tarot Made Easy" by Nancy Garen, and she describes the four suits thus:
Wands = ideas, original thought, intention, growth, ambition, expansion
Cups = emotion, desire, inner experience, spirit
Swords = action, movement, struggle, keenness
Pentacles = manifestation, realization, proof, prosperity, end result, fruition
If Wands represent "seeds," growth and expansion, how about Trees as a symbol?
The film has so many good examples of containers, maybe we could call the Cups category Vessels, allowing for buckets, coffee cups and pots, whiskey bottles and bean cans to be featured.
Given these descriptions, I think it makes more sense to assign the rifles to Swords. Maybe the suit could be called Tools, and could include the tire iron, shovel, rope, axe, spatula, frying pan, fishing rod, carving knife, etc., as well.
In thinking about Pentacles, it occurs to me that there is an example of a pentacle in the movie. The combine harvester visible in the Twist ranch outbuilding is the right shape, and its function matches the meaning given to it above.

Photo taken at the Twist house location in Alberta:

So what I'm throwing into the mix for the four suits are: Trees, Vessels, Tools and Reapers.