Find a local source, negotiate yourself a small margin above spot. Things to look for in a good source:
Lots of employees at the physical location ready to help (on busy days, you will not have to wait as long), available by phone and email, good online reviews, etc.
If you buy enough quantity at a time (only takes $5k-$10k per order to be a decent-sized buyer), you can get very close to the spot price.
