How to see library folder in Time Machine back up

Hi all! My hard drive crashed and burned a few weeks ago. Luckily, I had it all backed up.

So now I have my "new" computer up and running. I've set up Time Machine to back up this new computer. I have pretty much everything set up... except email. I have it set up, but would like to retrieve SOME emails from before my hard drive crashed (not all... I have so many I don't need).

The problem is... I can't see the library folder in my back ups. So I can't show Mail where to find the mail box folders.

I spent time on the phone with Apple Support last night... and they couldn't figure it out. I know the folder is there. I can do a search and find files within the library folder. I can see in the finder the path... and it is right where it should be. But I can't get Mail to see the library folder in order to pick and choose mbox files.