I assume the placards you are making are rather small, less than 12x12'' or so? In that case, any modern CNC mill should hold the tolerance that you need, mass and rigidity is key to making precise holes. Then it's just a matter of deciding on what production rate you need which will partly dictate the required work area in that you may be able to put several placards on the table and run them in batches. Then of course your budget will also partly dictate the machine that you buy.
Don't be afraid of buying a used CNC mill. You might look for a Haas (many models) or a Tormach 1100.