Here is a solution if you are using TortoiseSVN:
- In the repo browser, navigate to the parent folder of the folder you deleted (e.g. “branches”).
- Right click on the folder and do a “Show Log.”
- Find the revision where you deleted the specific branch folder.
- Select the revision immediately before that revision.
- Right click and choose “Browse Repository.” You are now looking at the state of the repository at the point in time right before you deleted the branch.
- Find the branch folder that you deleted, select, right-click, and choose “Copy to…”
- You can now copy the deleted folder to either a new name or even the same name.