It's a typical rookie mistake to confuse the cable costs with construction costs.
> And for three times that price you can get 144-count which isn't even remotely an option for subsea cables.
I know for a fact you can get 192 count subsea cable.
>> Subsea cable system costs are about 30k$ to 50k$ per kilometer.
> Including repeaters/amplifiers and power delivery?
Yes.
> Link?
http://letmegooglethat.com/?q=subsea+cable+system+cost+per+km
I know reading is hard, but repeat after me: "The reason you use 12 strands or less in long haul systems is that it is cheaper to use fewer strands and higher bandwidth rates per strand than to build high count subsea cable systems."
If you want high count subsea cable segments with amps, but which does not use in-line amps, take a look at https://crosslakefibre.ca/
To spell it out for you, subsea cables which are only a few hundred kilometers long do not require in-line amps, only head end amps.