>In order to get an FAA CPL/IR MEP you must have a full (stand alone) FAA PPL, since the FAA CPL/IR can't be issued on the basis of a foreign license.
Actually, you can. The prerequisites for a cpl include "Hold at least a private pilot certificate issued under this part" and a 61.75 faa seems to be quite acceptable as such.
However the rest of the advice is good. Lacking two points for the full story though, realistically avi_fun will have to enrol in a course and get an M1 visa. He will struggle to find anywhere that will offer a visa that allows a year or so work experience as a CFI. Once you factor in the cost of accommodation and a car, plus the risk of having to pay at least something upfront to a part 141 school for a course/visa, staying in Poland and getting an EASA CPL/CFI under the modular route might be a better option.