Article writing on get back ex & weight loss niche

Hi I am looking for an english language article writer who can write me 500 - 600 words articles for my blog & my seo campaign. The article is keyword specific & should be well optimized on keywords (not over optimized). The article for my blog is for 600 words & for my seo campaign is 500 words X 2 articles. I need the articles to be written for seo campaign (500 words X 2 articles) in a special way. The second article for seo campaign should be re - written sentence wise from first article. Both the articles need to unite in the article spinning {|} manner ie {First sentence of First article|First sentence of the second article} {Second sentence of the First article|Second sentence of the Second article} & so on. The submission for the article will be 600 words unique article, Two articles for seo campaign (each article in text format + spinned format as specified above). The first keyword is on trial basis as I need to judge the persons writting skills. I have lined up keywords for my new & old domains & researching more. I need a good writer to write in a prescribed time & unique content as I will check it in copy scape & if passes the test then only I will release the payment. I need the articles to be well researched on the topic & as specific to the keyword as possible. Certain time I will demand to add a sales pitch for a product at the end of the article. Thanks