The guitar is not yours, and it's rare. I think those two points alone should be enough to tell you that even for something as small as this, you shouldn't try to fix it yourself. I'd pay someone to do it. Plus, if part of the pickguard is lifting up, there's a chance that the glue underneath is starting to go, meaning someone might have to remove the pickguard, clean up the glue underneath, and re-glue it, which is not always as easy as it sounds because the finish can be easily damaged.
Quote by Ur all $h1t
On public transport I furiously masturbate while trying to make eye contact with as many people as possible for as long as possible.
Plus you should get permission from the owner before you do anything.

I wouldn't want anybody touching my guitar without my approval.