i need a banner for my website (www.kelleymether.com), which can be used on FB and on a business card

i need a banner that portrays my writing style. I am an author of romance/action/adventure novels. Most of my stories take place in war zones in the Middle East, Afghanistan, or South East Asia. The main characters work for a volunteer medical organisation, and there are escapes from various 'baddies', involving explosions (think IED's - improvised explosive devices) and my characters (male and female, mortal danger, in love) running from the explosions. My stories are NOT highly sexualised, so no bare overly-muscled male chests or large bouncing breasts. Nevertheless, characters are slim, good-looking, sexy while not being half undressed. No bright blondes, but female can be dark to golden chestnut hair colours, men black to golden brown haired. NO racial stereotyping of Muslim jihadists in turbans with rocket launchers. In my own mind I see a dusty bleak desert-style landscape, or rocky, dusty, mountains as in Afghanistan, an explosion in the background and male and female running, scared, hand-in-hand, towards the camera. The male is NOT carrying the female - she is no stupid screaming half-wit, it's quite likely she's just taken out two of the 'baddies' with their own guns. She is not wearing high heels, although she might be wearing a dirty dress or skirt. One of them might be wearing an item of clothing associated with hospitals/ medicine. I am looking at paying $350 AUD maximum.