As this contest is a bit different, maybe create some really awesome newborn shots that will really tug at the heartstrings of a new mom. Offer to do a few free shoots if you're new at this in exchange for model release, or gather some of your newest work that you have permission to use.  

Time to get shooting for samples. If you can't find the accessories you want, look for them on eBay and other online sources.

If you have an archive of images from previous shoots, get some permission from the families to use them for promo. I certainly wouldn't do it without consent. If not, offer a few free family portrait sessions as long as they agree in advance to you using them in promo of your business.

Start shooting or looking for sample images to use for this promotion

Lets get shooting and create awesome images for our promo.

If you don't have a suitable image for the Boudoir Gift Special, it's time to get shooting.  

If you have some images you can use for this promotion already, then great. But if not, it's time to get out the camera.  

Now's the time to get shooting if you don't already have your own sample images ready to go

Find some unique concepts and just as unique models to create some stunning B&W portratis

Go over your existing files and see which ones you want to use for the promo. Remember, you must have a model release and permission of the customer if you're going to show client work. If you don't have what you want, It's time to start shooting for samples. Pick something unique and plan on blowing away the competition.