Copy & Paste should do it.
I did a simple little test to verify this (and to re-aquaint myself to the different paste options). My original part was a body consisting of several sub-bodies with operations to remove and assemble. I right-clicked on the top body and copied it.
Then I created a new part.
I right-clicked on the part at the top of the new tree, and pasted. I got a new body with the exact features as the orginal, but with no links. Changes to one did not effect the other.
To continue the test, I right-clicked on the top part again, and did a PASTE SPECIAL and then clicked on As Specified in Part Document. Again I got a new body with exact features in the orginal, no links, and changes to one did not effect the other.
So, either of the above two methods work similiar to the old V4 Merge!
When I did a Paste Special and AsResultWithLink, I got a new body with a single solid that was linked back to the original part. When I changed the orginal, the second part updated with the same changes.
Finally, I did a Paste Special and As Result. This time I got a new body with an isolated solid (no sub-features). Changes to the original did not effect the copy, and I was unable to modify the copied solid.
Hope this helps you. ....Jack