Ah, scissors. Yes, you can get lef-thanded scissors, and left-handers can use right handed scissors in their left-hands - if we're not putting too much pressure on them (the blades will spring apart) and they're nice and shapr, however...
Try this, if you're right handed:
Take a piece of paper. Draw a mildly wavy line over it from one side to the other.
Take a pair of good, sharp right-handed scissors in your left-hand.
Cut the paper in two, following the line.
You'll find there's a blade in the way of you seeing the line to make an accurate cut.
Gordon