You need very few other ic's, for the keypad simply connect the rows to one port, the columns to another (choose ports wisely and you will not need pull up resistors). You take each column low in turn and then read the rows port if you have a low then you have a key pressed. The LED is very similar except you drive the common anode of the display with a couple of 74ls138 + transistor and the other segment pins with a darlington - say a uln2803 (you will probably need some current limiting resistors). the update speed for the display needs to be 20-30 updates per sec, any slower and you will see it flicker