Lance Assassin Farming

[The Kawaii Scouter]

So I've been really wanting a better specter COM for my Lilith but I turned in the mission for the Lance Assassins, thinking they'd still be able to respawn but they just don't. Is there any way for me to get them to respawn again or am I just done for?

I heard you can still get them from Crawmerax, although very rarely... is that true? If so then that's gonna be a pain to have to do as an alternative...