There's no way you actually sold that for $460...unless you have no concept of numbers or get the parts for free. The GTX 560's alone were worth over $300, the CPU $150, the case $50, PSU $50...it adds up to $700 in parts if I lowball it. You'd have parted it out long before selling it for $460.
Anyhow...I'll buy one for $500 if you're selling and can post your heatware. Alternatively, I'd also buy GTX 560Ti's if you sell those for $100 a pop.