Hit ebay for the armor. Ditch the velcro that comes with the kit and use "super velcro" from Home Depot or any crafts store.
Walmart usualy has their own version of Under Armour for the body suit. Get a mock neck top and if you can, heavyweight bottom. Reason for the heavier bottom is the legs take alot of abuse from the armor pinching. Expect to pay about $30.00 for the Walmart version, over double for actual Under Armour.
Shoes will also add another $70.00 to the price.
Gloves, you can use pretty much anything thats black but most prefer military style Nomex flight gloves. Anywhere from $15.00 and up.
all should be on ebay.