Copying another website

Unique content, good on page seo is what you need.

It doesn't matter about same lengths of paragraphs as they have.
Use different images though, so it doesn't look like a copy of their site.

Keywords, H1 etc, nothing wrong with targeting the exact same as they are - just make sure you're off page is strong enough to displace them.

What kind of spinner could you use that avoids penalties?

take the concept and rewrite it . You could outsource too when you say its easy to rank.