Where can I get polypropylene implants and what is the approximate cost?

There was some interest in polypropylene or string implants at one time as the continued expansion allowed some patients to achieve massive volumes. They are not currently approved by the FDA and therefore not available in this country. 

are not approved for use in the US.  How it works is concerning and often results in asymmetry.  Why would you choose this over the FDA approved gel implants?  If you're still set on them, you will have to travel to a surgeon in a country where they are allowed.  And if you have problems with them in the US, I'm pretty certain the only option you will be provided is complete removal of that implant.