Is 300 ml (Hyaluronic acid) enough for my hips? 150 each site? I go buttock implants but I looking for my hips (photo)

It is very difficult to determine the exact size and shape implant you will require to best match your ideal butt image without an examination by a board certified plastic surgeon. Not just any board certified plastic surgeon, but one with many years of frequently performing breast augmentation surgery including different approaches, techniques and implant choices. This is because several measurements not to mention your breast characteristics are needed to determine the optimal implant size to obtain your goals. Without knowing these dimensions it would be difficult to make this determination. For example, the existing base width of your buttock will determine, in many cases, the maximal volume per implant profile that you can accommodate. Liposuction of your lower back and fat transfer is also helpful as an adjunct to implants. Using “want to be” photos however are useful if simply provided to the surgeon.

Thank you for your question.  You would greatly benefit from liposuction of the lower back and flanks with a fat transfer to the hips.  This will help to reshape your body and give it an hourglass shape.  The goal would be to give you a smaller waist so that your hips will be more pronounced and your measurements will be more dramatic.  By just adding filler to your hips, it will not decrease the width of your waist and show very subtle results.  Not to mention that it will only last for a few months and cost you a pretty penny.  Be sure to choose a Board Certified Plastic Surgeon that has a extensive experience with such procedures. 

I have unfortunately had many patients come to me after having their high hopes for buttock augmentation crushed by measly Sculptra results or other "fillers". Critical points of awareness are: 1) Sculptra is temporary, it will last 1.5 - 2 years at most, 2) if done correctly dermal fillers like Sculptra are cost prohibitive for 99% of potential buttock augmentation patients. In order to create a significant/noticeable result with a dermal filler, at least 200 mls of product must be injected into each buttock cheek for a total of 400 mls. At $1000 per ml, this equates to a minimum price of $400,000.00. Thus if your doctor is recommending to put in ONLY 20 or 40 mls of sculpture you will pay $20,000-$40,000 and get an insignificant miniscule result!, 3) Do not let anybody tell you that the product is so special that it's going to magically grow over the following months or years...this just doesnt happen to any noticeable degree!, 4) dermal fillers, when injected in large quantities, have a relatively high infection rate, guaranteed tendency to migrate away from the original area they were injected into, and almost always stimulate a lot of inflammation with a subsequent and disastrous amount of scar tissue/hardening, and 5) the one very serious complication that can rarely (< 1%) happen is "embolism" in which some of the filler gets into the blood stream and travels up into the lungs, heart, and/or brain causing serious problems, including death. 
Hope I at least saved you some money and maybe even your life.