You should be able to buy them throughout the game or just find them. I had plenty as I played through it, when I ran out though at times I would just nuke the chest until it exploded and the loot what falls out or in the example of that same chest you mentioned I teleported it from it's position to another spot in the room and when clicked on it in it's new spot it opened without need for the key.
Last edited by Dragoonlordz; 09/07/14 07:49 AM.
