According to Babs Chula, who was speaking after the film's premiere at the Vancouver International Film Festival, "Seven Times Lucky" is the name of the winning horse in the race that Harlan bets on. In the deleted alternate ending, "Seven Times Lucky" is the name of a horse that Uncle Harry suggests in an upcoming race.
There is purposely no discernible timeframe for the movie. There are '70s and '80s cars and rotary dial phones coupled with the latest cellphones.