No. There’s a way to know about what it is (within a point or two), but not the exact ranking. That’s Google’s little secret. Proof of concept: I saw a site yesterday that had four PR icons at the bottom. Pointless? Yes. And there were two different PR’s shown between them.
I quit worrying about PR; I just focus on content now. Some of my “PR 0” pages often turn up in the top 5 for their target SERP. And this is the big misunderstanding: PR has nothing to do with how well your site ranks in the SERPs; it has only to do with how much love you can give in a link.
It’s my theory that there is a second rank assigned to the page which determines its strength of association with a particular search phrase. And that’s what makes you come up on the first page. It’s all about content.