Native content writers - USA , UK

Hello freelancer, I am looking to hire some native content writers from USA, UK for content writing services. I'll prefer to work with versatile content writer who have an experienced with multiple content writing styles like web copy, sales page, informative content, press release etc. I need writers from USA and UK who can generate High quality research base and grammatical error free content. I've fix budget of $2.5 per 500 words content. Negotiation not possible. This is long term writing job and writer must be able to write up at least 5 content per day. Please send me proposal if you can fulfill above condition. Thank you,