Cavani,Falcao,Levadonovski all tree of them have been available on market this summer.
If Arsenal wanted to pay 50-60m I am sure that for example Falcao will rather play in Premiership then in France.
Cavani and Falcao have just moved clubs and are on wages that Arsenal definitely wouldn't pay. Lewandowski is holding on for a move to Bayern next year. None of them three players you have mentioned are feasible transfers for Arsenal.