Did it today and it works
I decided to ground the unused inputs just to be safe, but it seemed to be ok without grounding them.

Yep, hc14 should be alright.

Edit: Unless hc14's are so slow that they can't keep up with video signal. That, I haven't investigated.

I already have some of these.

Edit:
After thinking about this, there's no real reason why it shouldn't work.

why do you want to use a 74hc14?

So I checked bibbin's blog, nitro2k01's blog and nonfinite's store and they all seem to use 74hc04 for their screen biversion.
Will it be ok if I use 74hc14? According to this the only difference is that the 74hc14 uses schmitt triggers instead.
So will 74hc14 work fine?