According to the following post:
http://davidvg.com/2011/12/07/converting-a-git-repo-to-svn
a git repo can be converted to an svn repo using hg convert. This works for me, however, the resulting svn repo is to modern for me. The db/format number for the resulting svn repo is 6 (svn 1.8+). I need it to be 4 (1.6+), an older version of svn that is. Is there a way to specify for hg convert to convert to a specified db/format number?
Or, is there another way for me to convert my git repo to svn db/format 4 (1.6+)?
You can use a current version of Subversion to dump the repository into a version-agnostic format (svnadmin dump), then use the older version of Subversion to load that dumpfile into a new repository (svnadmin load).
Otherwise, I would suggest finding older versions of the hg & git based tools that support that older version of Subversion.