Does anybody know where to find a cutting tool like this? I'll start looking at art supply shops.

I used to see those some where, I think it was at a paint and wallpaper store. That may be a place to start.

look at discount places, you usually get these thing in a bigger pack with a lot of other retractable knife's for 1 or 2 bucks.

I used to use those when I was in the model building years ago. Got them a a craft store. I still see them at Hobby Lobby or Micheals.

good luck hunting.

ive seen them in hardware stores at the counter in plastic buckets.