You typically get what you pay for when it comes to backlinks. Especially if you search for "high PR backlinks." You may have had a bad experience if you've hired vendors based on that term. Google discontinued its "PageRank" ranking tool several years ago, so that concept no longer has any meaning. Today, Google looks for contextual links from high authority sites that are relevant to your "money site." If a vendor is still advertising "high PR links," they probably aren't any good at SEO in the first place.

I am not recommending this particular vendor, because I haven't worked with them before, but if I were to buy links, I would look for the level of detail you see in this person's service description: http://www.konker.io/services/2906?affid=245f87 They have an understanding of the current state of SEO.

If you have any questions about your SEO strategy, I would be happy to give you an SEO reality check. Just give me a call.