Hopefully you live in a major city to avoid postage. Cheapest parts are going to generally come from MSY, Umart and megabuy. It really doesnt matter, if its faulty theyll all refund/swap or send for repair if not DOA. (most pc faults are DOA parts, generally if its working out of the box itll work longer than its waranty period)
Do staticice.com for part prices.
One thing to possibly change for an extra $10-$15 is the power supply (not that the fractal is bad). This antec is top rated and gives more overhead for future GPU purchaces - Antec HCG-620M