How many of each item card type am i supposed to have within the base game? I feel that I may be missing some but I cannot find a definite answer anywhere.
Looks like for the base game you should have 120 Item cards consisting of:
16 Purple round item cards
30 Blue square item cards
46 White triangle item cards
28 Special item cards
For reference, if you check the "Community Wiki" entry for a game it usually has component information, that's where I grabbed this from.