Lets see...
2 bus bars at approx 1lb each (for argument's sake) = 32oz x $1574.60 = $50,387.20 for gold bus bars...
For Silver, make it $907.52
(these are just trading prices... weekend trading prices at that)
For Aluminum (scrap price $0.89 PER POUND, lets triple it for retail) So $5.34 but I'm sure it costs more than that
Doesn't make much sense to put more cash into the bus bars than the rest of the system. But do what you want, I won't judge
EDIT: Platinum bus bars would be cheaper than gold, $48,888.