I ended sewing it by myself, total cost: $18. I used a pattern! My first time using one, and I discovered that it's much easier making clothes with a pattern than doing them 'by eye'. I used New Look 6750.
PS: The sleeves are really nice but can't be seen on the picture, they are done with two pieces of fabric, front one in grey and the back one in black
Finished and ready to go:

I hadn't finished it in this picture, still had to adjust, sew and serge (I bought a serger a few months ago and I LOVE it) but you can see the details on the sleeve and the bodice:

























