I was unable to find a way to put the results in quick or local search lists, although I'm sure you can extend Unite to include this action.
Meanwhile, this short excerpt from the Unite documentation can help you reopen the recently opened Unite buffer:
:UniteResume [{options}] [{buffer-name}] *:UniteResume* Reuses the unite buffer named {buffer-name} that you opened previously. Narrowing texts or candidates are as-is. If {options} are given, context information gets overridden. Note: Reuses the last unite buffer you used in current tab if you skip specifying {buffer-name}.
I use this as follows in my vimrc:
" Press <leader>ll to re-open last Unite buffer nnoremap <silent><leader>ll :<Cu>UniteResume<CR>
Another useful snippet from the docs:
-no-quit Doesn't close unite buffer after firing an action. Unless you specify it, a unite buffer gets closed when you selected an action which is "is_quit". -keep-focus Keep the focus on a unite buffer after firing an action. Note: This option is used with "-no-quit" option.
For example, you can snap
nnoremap <silent><leader>lg :<Cu>Unite -no-quit -keep-focus grep<CR>
To press <leader>lg on grep through the source files without closing or defocusing the Unite buffer when an item is selected.
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