Getting a 28,800 bph movement is not a problem, this will give the same smoothness of ticking on the dial as Rolex submariner. You can use a ETA, Sellita, or some of the Chinese clones of the ETA that have the same occilation frequency.
You need to have the following characteristics to mimic a Rolex Submariner movement:
28,800 beats per hour - 8hz
hacking - means the sweep second hand stops when the crown is pulled out to the fullest extent
hand winding with some smoothness - can't feel or sound like a cheap toy car.
Rotor that winds the mainspring from the movement of the rotor in either CCW or CW direction
An ETA or Sellita will be $120 to $200 and the Chinese clones are about 40% of the ETA or Sellita movements. Miyota (Citizen) make their 9xxx series movements with same frequency as Rolex, but these are easy to identify because the automatic rotor only winds in one direction, the rotor free wheels in the opposite.
I have seen very high calibre copies of the Rolex movement, the Chinese have copied EVERYTHING in a Rolex 3135 movement, down to the perlage on the movement plates. When you open up one of these expensive replicas most watchmakers would feel confident to say they are looking at a real Rolex. For this reason, the sourcing of a used genuine Rolex is very risky. You must do your homework, and buy the SELLER, not the watch.