I didn't have very much time to get a wedding dress with my short engagement, but I found a really good one from a designer on Etsy. It fit the bill: modest, simple, long-sleeved, pretty, not too expensive, great reviews, and, perhaps most importantly, it would get here at least a few weeks before the wedding. That last point, however, turned into a bit of a fiasco because the dress got stuck in shipping in Poland, so they made me another dress and FedExed it to me directly with less than a month to go before the big day (at no extra cost to me). It went from Kazakhstan to Dubai to France to Boston, and it arrived a little less than two weeks before the wedding, with just enough time for me to have alterations done.
Phew! It all worked out, and fortunately, I loved the dress. I'm going to have it made into a temple dress so that I can wear it several times a year for the rest of my life. I'll post pictures of me wearing the dress on my wedding day in a month or two, but for now, here are the internet pictures I saved on my phone after buying it in early August.