You can call and ask the receptionist if they are lookin' for freelance or fulltime editors. Sometimes asking for the post-supervisor is a bit spammish but I've certainly done it. I've never landed a gig from the place I was calling this way but was referred to a place that was looking doing just this and got the gig.
Don't be shy. Throw it out there and see what happens. While I may have used a reel or two as dub stock in my day, I've never cussed anyone for sendin' it.
