i have to find a new dress!

I really hope everyone elses wedding planing is going way smoother then mine.

I need help. I found out last week that my dress with cost $650 to $850 more for alterations when I was originally quoted $300. My budget for a dress was $1000. Or a little higher just not that much higher. Im very petite and i know im going to need alterations regardless so I'm prepared but not for an extra almost $1000.
The dress was an Allison Webb dress and it was on sale off the rack and I loved it. During my wait and working extra hours to get all the money for it I was looking at other dresses just in case I could meet the deadline but I did meet it. And Im heartbroken about the news. I changed my bridesmaids dress color to suit the dress and was reluctant to do so and a bridesmaid already ordered her dress and I cant do anything about it but just change the color. I need help figuring out where to find another dress and where to find it online thats around that price range. If not 1000 then im willing to go Max 1400 for a new dress im going to order to fit me with minor alterations. Ive looked almost everywhere and I just can find a dress I love. I'm thinking of having a fitted dress with a detachable skirt or a aline dress with extra material under to look like a princess gown but not a ball gown that will swallow me. I'm 5'2 and a petite 0 or 00 and weight under 100lbs. Im tiny! But want to feel like a lady for once on my wedding day. Any suggestions?