9 post? check
$500 in BTC? check
Paying with reversible funds? check
Right ... puffn, if you weren't aware, there are plenty of methods to purchase bitcoins using cash -- deposited at a bank, or at a 7-11, Walmart, CVS, etc.
(deposit at Chase bank, no fee)
(deposit at major banks, 7-11, Walmart, CVS, etc. (in the U.S., or in Brazil, Boletto or Banco Recomendito, or in Russia Qiwi or Cyberplat)
(in Canada, deposit cash at several banks)
(in Australia, deposit cash at several banks)
(in India, deposit cash at HDFC)
(buy CashU cards in the Middle East, or buy UKash vouchers in Central and South America, dozens of other countries).
Also, there are local traders:
If you must go with gift cards, Get-Bitcoin will take them. You mail them in, and after they are spent successfully the bitcoins are released.
There are a lot of options: