Wife is away- buy goldfish- help

Need every ones advice. I have a waterfall emptying into a 3' x 3' x
24" "pond". No filtration because I have only used it for it's
aesthetics and sound.(and because I have two curious Labs)

BUT, my wife is out of town and I have been dying to put in two
goldfish(of some kind)

a) is there enough bacteria in the water now so that I do not need
filtration?
b) will they be able to hide from the Labs?
c) what type would you recommend?

Hurry, she's back in four hours ;-}

PS Don't worry. I will not rush into anything. I would not want to
buy fish to have them stressed out or die because of poor planning.

All the best,

Larry