How long can an extracted tooth be left without an implant?

I just had a tooth extraction. I need to get an implant done but since it is very costly here in the US, I want to go to India for implantation. How long can the extracted tooth portion be left without an implant? Can I get an implant done after a year or year and a half?

 

There should be no problem in waiting a year and a half to get the Implant done although the norm is to replace a tooth earlier rather than later.