Another option is restaurant supply stores. You can find a lot of good used stuff. A friend of mine had a 6 soda Pepsi fountain like the older ones you would see in a Taco Bell etc.. He had the entire setup machine, pump, co2, syrup rack etc for under $1000.
I realize you're looking for a gun type dispenser, I'm just trying to give you an example.
As far as using a lot of ice etc.. Most places incorporate the distribution plate the syrups run through into their ice machine. There are a number if creative ways to mount that. An example would be if your dad already has an ice machine for his setup or a standard refrigerator; the plate could be mounted inside etc. it's not that difficult, slightly more complicated than a kegerator setup.