There are usually no 3rd party replacements for laptop heatsinks/fans. Even if there are, it is usually an exact model that HP produces as the market for these goods are often not large enough. With every laptop heatsink different in shape and dimension, there is no one size fits all approach that you would find in desktop heatsinks.
If the reason for asking is that it is overheating, it is best to dismantle and service the heatsink which might be clogged with dust. It is also possible to gain lower temps by replacing the thermal paste. Having done this in the past, it might require a total dismantling of the laptop to get to the fan.
Acer is one of the few that makes fan maintenance/replacement easy. Not quite sure about HP but I do remember having to do a total dismantle of a Dell laptop to clean the dust.