I would like to hire a Game Designer

No idea how much these cost. I am a novice book writer (civil surveyor by trade). Ive written and published 3 books and my fourth book (completed in late 2017) is called 'The flying Shetland sheepdog'. Based in WW1, it focuses on the pilots in the sky. BUT... instead of humans, its dogs. So its basically the british, American, French and Australian breed dogs (Shetland Sheepdogs, British Bulldogs, French Poodle) VS the German ones (German Sheppards, Dobermans, Schanuzer etc). See where I am going with this? Anyways, I want to create a short iphone/ipad game to accompany the book. I remember a game from the 90's called the "Red Baron". Look it up on youtube. I want something similar created but with better graphics. Basically its all about dogfighting other planes. Happy to have 15 missions (one where you have to take out a zeppelin, maybe one where you have to take out some bombers and others where you have to take out a observation balloon, but mainly its dogfighting). The more planes you take out, the more medals you are awarded. As you increase your skill, you get to choose your areoplanes (upgrades) - that have better manouvring and go faster. You can even choose your paint colour. Anyways, that's where im thinking. Can anyone help?