Stroker kit..440 Source or Eagle?

Either one is fine but neither should be ordered balanced or run "out of the box". The rods should be cycled and big ends checked, the small ends properly honed to fit the pins, the cranks should be very carefully measured to make sure the taper they more-than-likely will have is acceptable or not, and the crank snout should be measured to make sure the balancer will fit properly.