I think you can and it is actually really easy to try. Just give yourself 2 bikes with Kernel.pbReceiveItem(:BICYCLE)
I tried and actually you always have only one if the item is not a one use. So when you define the item in pbs the last number must not be 6, for key item. However the number which says in which pocket the item is stored is another one so you can have pokeball in key item pocket.