You will need 25 rounds per stage X 8 will equal 200 rounds WITHOUT ANY MISSES!
There are 5 targets per string X 5 strings per stage (25) rounds
As to equipment wait and see what the other competitors are using and ask questions. 2 magazines should get you through each stage
NRA Life Member, NRA Range Safety Officer, NRA Certified Pistol Instructor, IDPA Safety Officer, USPSA NROI Range Officer,
ICORE Range Officer
As you are, I once was, As I am, You will be.