You can also use the containers corn and saflower oils come in. Although I'd clean them out with some alcolhol the truth is they'd blend in just fine. I remember guys burning mentanol-corn oil or olive oil in their .049's years ago as an alternative to castor. I doubt a little bit left in a container would have a noticeable impact but swishing around some alcohol to clean it out is just too easy to do.

Regards,

Clay