why don't you just sweep your private keys into a different wallet and try to resend?
Because the issue is unrelated to the wallet, thus sweeping will not work (as it creates a TX) and neither will importing (you will have the same problem). I think the only way to still use these coins is to spend them with larger inputs, according to my estimates it will still result in an overall loss of coins unless the network fee gets significantly lower (~half)[1!]. I played with the idea of buying OPs private keys and just doing it myself.[2]
afaik armory allows export of the private keys through -"Backup This Wallet" - option "Export Key Lists" (must have adveanced options on)
this will show you your addresses and corresponding private keys
then download Electrum or use any other wallet that supports private keys import
with Electrum you should paste your keys into Sweep Private Keys box
and then try to send your transaction again,it should not cost over 0.001 bitcoins
500 inputs worth 0.0001 each currently cost more than 0.005 to spend. Cointape right now suggests 180 satoshi per byte for a timely confirmation. Each input weights 180 bytes and is worth 0.0001, thus the fee needed to spend each input is 3 times as high as the inputs value.
tl;dr: 180*180/10^8 > 0.0001
[1] apparently it increased since my last calculation, see below for the second part.
[2] @emsi feel free to contact me via PM about this.