Actually you dont have to hunt imperials to get these. Run Beldonna missions on corellia. You get them no problem. And at a lot higher rate then they drop off stormtroopers.
"You're part of the Rebel Alliance and a traitor. Take her away!" Darth Vader -
'I beg your pardon, but what do you mean: naked?' - C-3PO
Drav Troelle - Scylla - Colonel in the Rebel Alliance