I'm speaking more from an iphone experience, but it should be about the same. If you're still in your native country and can find out if the ipad is locked to your current network, sometimes they will unlock it for you for a charge, otherwise you'll have to go the alternate route.
If it is locked to your current network, you can not simply purchase a Claro, Movistar or any other chip and have the device access that network. It will have to be "jailbroken". You may also need to cut down the Claro, Movistar SIM. The one I have is still the standard size and iirc the ipad uses microSIM.
If you discover that you'll need to cut the SIM, and you're still in your native country, purchase a cutter on ebay.