Anchor if you wanted to know
About the dress, I'll get back to you on that since it slipped my mind. My mom was more involved in the dress then me but I can ask my sister to take out her dress and take some pictures for me.
As for the anchor, I was a big part in that I can help you there.
Some reference:
http://www.cosplay.com/photo/1571916/So there are a lot of things that should be fixed with that, but my handcuff was my first prop and my sis's anchor was her's so it's a good first shot!
Anyways what we did was we bought a bunch of upholstery foam and used that for the top circle, the the long thing (name slipped my mind!) and the lower circle thing. You just cut out a basic shape you want, then you use a crap ton of masking tape and tape it up so you get a more rounded shape if that makes any sense. Then you go over each part with brown packing paper and glue (just use it like paper mache). For the actual bottom part I can't remember if we used more upholstery foam or cardboard but I'm sure either would work. If it's upholstry foam, just do what I said earlier. Anyways, as you can see her anchor looks lumpy. She rushed on some parts of it which cause it to look gross. I suggest going over it after it dries with layers of gesso and sanding it the hell down.
I know this is a little confusing but I can pm you with a more thoughtful tutorial if you'd like.