craftgrrl | Where can i find top-quality fabric for a wedding dress? (Reply)

I'm not sure how relevant this question is for this community, so if it's out of place, just let me know and I'll delete it.

I'm looking for a place (either online, or in Northern California) that sells top-of-the-line silk fabric. Can anyone offer some suggestions?

A good friend of mine is getting married this summer, and I'm the bride-of-honor. She's not well-off, and will have a low-key wedding...but when she mentioned going to Walmart to look for a dress, I realized that someone need to intervene. The other bridesmaids and I are going to pool together some money to have a really GOOD wedding dress made for her. While we're hunting for a tailor (my sewing skills are strong and I'm making most of the bridesmaid dresses, but I don't trust myself with something like this), I want to purchase the best fabrics possible for her dress. We're leaning towards a simple but elegant sihoutte in silvery-white...it would go beautifully with her skintone, and it doesn't scream "wedding" so loudly that she can't wear it in the future.

I'm thinking of going with some form of silk--something that's very strong and doesn't snag easily (so no silk chiffon), but has a soft drape (no silk faille either) and a touch of lustre. Any suggestions (both/either on the website/store, or the type of silk that I should look into)? Also, roughly how much fabric will I need? We're looking at a halter neck, open-back, A-line dress, double-layered. It will probably sweep the ground, but cut in a way that she can have it hemmed afterwards at the knee (so how often DO you wear a floor-length dress anyway?) She's about 5'4 and less then 100 lbs. I really appreciate the help!