Tetanus is readily available by itself.
D and P are usually bundled (with T) but as I recall P is available by itself ( it’s been a while, could be that my kids were forced to get the D in order to get the P)
D and T are readily available together. It’s common for people to request these two as Pertussis is the one responsible for fever and subsequent seizures.
I don’t know if D is available separately.