Another training tip/trick.
Get your local butcher to give you meat that is out of date that they are throwing away. If it's not free, it's stupid cheap. Gash it, shoot it, stab it, fix it.
To practice chest decompression, get a rack of ribs, a bicycle tube, and cellophane. Inflate the tube, put it under the ribs, and wrap with cellophane. Then you can count the ribs and needle the 'chest', get the air escape (a la tension pneumo). Tape the hole, reinflate, do it again.
When I teach the local butcher would usually give me expired ribs and meat for these.