Build 50 Authority Backlinks from PR4+ websites

I own a network of blogs and i am looking for some one who can build backlinks for my website regularly. I would be starting with a small project of 50 backlinks that i would want you to build. All the domains should have atleast PR4+ and have an authority not gained its PR by domain redirect. I would be giving u the anchor text and would want the links to be placed on first page of the sites. All the link building work needs to be done ethically and manually. Please also let me know the sites u would be placing links on along with the bid.