Unless you really need high speed, I always recommend going totally 4xxx series. Much less critical on layout etc, and you can use un-stabilised supplies anywhere between 3 and 15V.
BTW a crude but effective switch de-bounce consists of a series 100k resistor and shunt 100nF cap feeding one of the inputs of a 40106. This sort of thing is also commonly used to provide a degree of static protection for inputs that may be 'floated'.
It wasn't me!
(Well, actually, it probably was)