Need a motor

you could go with a 1600-2000kv motor, either Neu or Medusa
Medusa-70mm
Neu - 2d, 2.5d, 1.5y

or if you are feeling randy a 1521/1y (1500kv) you would be able to gear up more with this motor but you will need to measure it will be a little longer than a 1515 can