Well 4000 series CMOS will work with 12 volts, that's not the problem. Lamps typically require more current than LEDs. I seriously doubt you could get a 4000 series part to drive a lamp directly. A transistor driver would solve that problem.
Lamps also get cranky when you hit a cold filament with a surge of current. You might want to consider keeping the filaments warm but not illuminated.
Last problem. You want to expand the circuit from four buttons to six buttons. Some of the lines on your schematic are invisible so I can only guess at what you are trying to do. A RESET clears(set) the D flip-flops so that all the LEDs(lamps) are off. The first switch to be depressed sets(clears) its associated flip-flop AND locks out all the other flip-flops. This can be represented by a straight forward set of boolean equations which I leave you to work out.