1- Non US card. But sure you can use for US billing.
Sorry but that's not true. Many US stores specially want the billing address to be in of US or else they will decline the order straight away. I am looking to buy a VCC that works for Walmart online. If yours work then you can expect around $300-$500 worth VCC from me.
If its possible can you check buying from walmart.com using your VCC? You can try buying a $5 egift card. If it works I will buy that egift card and also the VCC from you straightaway. Let me know.