ASOS is one of my go-to brands for items that fit without alterations, plus they offer free international shipping for orders over $40 & free returns which is awesome. Quality can be hit or miss and sizing can be tricky (can run 1-2 sizes small compared to American brands). What adds to the confusion is ASOS sells both their in-house brand (ASOS regular, petites, tall, plus, etc), as well as tons of other brands, so sizing and quality will differ across all of these brands. However, when you do find winners, they tend to be gems that you won't see on everyone else.
Instagram friends have already seen this lace dress, which is one of my favorite pieces ever from ASOS...
I'm wearing a US size 1 and it fits like a glove (every time I see the word "bodycon" I automatically order a size up than I would for other ASOS items). For fit reference, my measurements are 32-24-32 with a 30A-32A bust size. It feels smaller than a 00 petite in American brands and similar to an H&M size 2. Here are a few other adorable dress options available in all petite sizing:
Lastly, I recently discovered a British shoe brand, Dune, and am in love with my jeweled sandals. The crystals aren't everyone's cup of tea, but I must've gotten a dozen compliments and inquiries the day I broke these out. I initially discovered this brand out at an industry conference and thought the products on display were nice quality. You can find these same shoes on their website in a number of colors (just type "Harah" in their site search box - the international language conversion doesn't allow me to link to the specific product). Unfortunately for small-footed ladies, the smallest size they make is a EUR36 which they say translates into a US 5, but I do find that it fits more like a US 6 or generous 5.5. These are a little loose on me, not bad because I usually straddle 5-5.5, but would be too roomy for someone who is a true size 5. I also wanted to mention that ASOS carries a few of their styles, including a very similar version of these sandals!