I'd like to send an unsolicited email to a couple of businessses in my community asking them if they'd like to contribute something about their business for a community blog. Is there any legal/legitmate way to do this? If I add the unsubscribe verbage at the end of the email, does that make this one-time email legal?

Being that it's a one-time email, it seems strange to ask them if they'd like to unsubscribe, since they aren't being subscribed. I look forward to being enlightened, thanks.