You can use the svnadmin dump and load commands to move a repository into a different repository.
If you have changes in your local copy, commit them otherwise they'll not be in the dump file hence will not be loaded into the other repository.
To move /home/steph/repositories/repos_one into /home/steph/repos_two:
svnadmin dump /home/steph/repositories/repos_one > repos_one.dump svnadmin load /home/steph/repositories/repos_two < repos_one.dump
If you would like to move the repository into a directory in the other repository, first create the directory and then do the dump and load:
svn mkdir file:///home/steph/repositories/repos_two/one -m 'Added directory for old repos one.' svnadmin dump /home/steph/repositories/repos_one > repos_one.dump svnadmin load /home/steph/repositories/repos_two --parent-dir one < repos_one.dump
References
Subversion FAQ - How do I merge two completely separate repositories?
