Afraid of losing SERP and PR..

I have recently bought a website running a wordpress blog. The deal includes both the domain name and its content. We've started by transferring the domain name and everything went great. Suddenly, the person who i bought the website from asked for more money if I want the content, which was included in the deal. Of course the content is worthless for everyone but me since both I and the seller know how much the content is important for PR and SERP..

My questions are:
1 Is there a way to retrieve the content and move it to another wordpress blog in my server knowing that I only have access as an author in the current WordPress blog.
2 If not, I have already downloaded a copy of the whole website using httrack, how can I have this put in a sub directory in my new site and redirect all search engine visits to the subdirectory while having different content in my main site.. all without losing google PR and SERP?

example: moving the content that was in mywebsite . com before buying the website to mywebsite . com/content now.

I have done few searches and found some info about .httaccess, but I don't want to redirect all my visitors. I'd like only search engines and all previous blogs linking to my content to be redirected to the subdirectory.

Any help would be appreciated.
Thanks!