I need something thats hard to cut or rip and waterproof.
They make rain bibs(carhartt and others) I keep them in the van and slide them over my work clothes. Over that just a good solid rain jacket, you could go the cheap route so if it gets torn up it's no biggie but I have a carhartt one that ran about $50 dollars with reinforced elbows.
If it's an extended period on one unit, you could go for a pop up cover that would shield you and the work area.
I bet somebody in Washington or Oregon would have it down.
I wear this very light weight jacket that breathes I forget the name. Wal-Mart has it for like 30 bucks. Pvc type material for pants only because I've yet to buy better. I was in the rain 8 hrs yesterday. Poured all day but I was dry underneath. I typically don't work in the rain but wasn't doing anything that had my tools involved. Did a couple hundred filters as part of a PM