CMOS IC help!
 

This is a 4-bit Magnitude Comparator.

The 7485 (or 74LS85) is pin-for-pin compatible.

The only thing is the Vcc power supply will have to be limited to 5
Volts. If this chip is connected to external inputs, they will have to
be TTL compatible, also.

Digi-Key sells both parts 4063B & 75LS85 (but I didn't check their
stock-on-hand).