Just to clear out a few things, Yes the platters can be changed but the cost of the tools needed to perform this swarp is over 400$, I did the research because I once encountered the same issue.
This issue is caused by the read heads is damaged, the disk spins up to the required speed, the heads go into the disks, because of friction the disk looses speed, to restore the speed and recent read errors it parks the read heads and spins up again, after a few attempts it will give up.
To remove the read head and the arm without damaging or bending them(which will happen if you do not use the correct tools due to the "microscopical" precision needed) you need something called a headcomb, depending on the model and brand of the HDD you will need different headcombs, such tools are very costly, for the disks you also need a special tool to prevent scratches an contamination which will corrode and damage the disks.
As for breaking the airtight seal, its not as bad as people make it, the speed of the disks will throw off the dust and there is a filter to pick up any particles that may occur.
You can pay repair services to make a diskswap for you, but unfortunately that too are costly.
