I've done a few of these things using offcuts from various places. Sometimes it works sometimes it doesn't. I like the way it allows you to keep a lot of the figuring that would otherwise get turned out.
The first one is approx 9" long at 4" at it's widest, secoind is approx 5" long & 3" wide. I don't square them up, just plane and sand the edges smnooth. Leave the shape whatever it is. Done a few triangle ones as well, have to watch your knuckles with those as the ghost is hard to see.