You could use trackable for those that can be labelled, and not trackable, nontrackable, or untrackable for those that can.
Adj. 1.trackable - capable of being traced or tracked;
Although now that I've typed untrackable, untraceable comes to mind, but I'm not sure it means quite what you want.
EDIT(side note: I've just noticed the site I linked lists traceable as an alternative)
While responding to the comment below, I realized a very workable word for this is indexed for those itmes which are labelled/numbered (and non-indexed for those which are not).
Since you have many of each type of item, and are using the barcodes to differentiate between the barcoded items, you could use the terms unique and generic.