Petite Jeans inseam 28 " is equal to 71 cm. The higher that number is the easier it is finding them. Fingers crossed, you find yours very soon.
Here are some 28" inseam jeans that I found online for you to look through. Don't be put off with any prices in the UK pounds if you are from the US and vice versa. Most of the stores ship internationally.
If you can't find them here, then go to the list of Petite Clothing Stores that carry inseam 28" and check the stores yourself. Good luck in any case.
Got 6PM main page. Under Women's category pick Denim. Then pick the size, color, brand and any other criterion you want to narrow down your search to. Easy? Very. Now pick your 28" jeans out of hundreds they offer.
Dorothy Perkins petite jeans do have your inseam size jeans too. You need to click on the jeans image to see the product details that shows the inside leg length.
Loft Petite Denim. Want super skinny, skinny, straight, bootcut, flare or boyfriend jeans? You name it - Loft has got it. Choose out of tens of jeans.
Zappos petite jeans section has all women's jeans categorised by inseam sizes, which makes it really easy when you are searching for yours among hundreds of other sizes.