merging 2 iTunes 12 libraries

I lost my entire iTunes library (don't ask) and by the time I realized it, the backup had been overwritten (don't ask). I am now reimporting my entire CD collection into a new iTunes library. No biggie other than time, except that the iMac I'm using is quite old and the CD drive is getting a little flakey. I have some CDs that import on the first try, some on the 3rd or 4th try, and some that the CD drive can't read. Brilliant idea - I could spend $79 and buy a superdrive and use that. But to check to be sure that it's my drive, I took some CDs that couldn't be read and importing them on my MacBookPro. No problem reading them at all, so now I know the problem is the CD drive. Then I thought, why buy anything? I have home sharing turned on - I can just import the CD from the MacBookPro into the shared iTunes library that physically resides on my iMac.

Except that it doesn't appear that I can actually do this. I tried to see how I can merge 2 iTunes libraries and come up with nothing. I tried to see how I can move music from one library to another and come up with nothing.

Can anyone suggest anything? I don't really mind buying the superdrive if I really need to. The real solution is to replace my old iMac, but it needs to be a little more dead than just a flakey CD drive to make me do it.

Thanks for any help.