Forgive me if I come off as being a dick, but personally I would never accept a gig, ESPECIALLY a wedding, if I were this unprepared with only a month beforehand. A wedding is a big deal for everyone involved, and the last thing they want is a ****-up, even with the entertainment.
IMO, no, 7 effects is not enough. Sure, you'll probably be doing brief sets like mentioned, but the minimum I think one should have is 10-12 SOLID pieces of magic in their arsenal at any given time. Who knows if you'll have tables calling you back, or people that have already seen you, gathering around to watch a bit more magic every now and again. It's not always the case, but I personally feel only 7 solid tricks isn't much to play with.
Secondly, stay away from any cheesy jokes using the bride and grooms rings, them, etc. You're the entertainment, not there to crack jokes at their expense. Chances are, they wouldn't go over too well. Anyone recommending that is just doing so out of ignorance (just not knowing), not experience.
Thirdly, when doing a large strolling gig, I always carry 2 decks and 2 sharpies. Just to carry one is not a good idea, and is something I've had the learn the hard way. Also carry additional business cards on you, but I tend to not pass them out unless asked for at those kinds of events. What I have found to be successful is oftentimes, there will be a couple tables outside the reception hall. One with pictures of the bride/groom, and another with hotel info, wedding info, etc. I have a business card holder that I sit on that table, and put some business cards in that. But only do so with permission.
Anyways, just some thoughts. I still think you're going into this under-prepared with limited time left. Not something I'd do in a million years, but it's whatever.
Best.
Steve