Here is a nice list of cruelty-free mascaras with reviews (some are vegan as well). I personally am a big fan of NYX products as they are affordable, effective, also have all the crazy colors you need for cosplay, and are cruelty-free. Essence brand, found at ULTA and one of my favorite budget-brands, also is affordable and cruelty-free. Their waterproof mascara is pretty amazing.
Concerning mascara, keep in mind, the models are also wearing false lashes in 99% of the mascara ads you see so if you really want amped up volume and/or length, you can always get some falsies to further boost your look.