Starting with Git 2.5.0 (which needs to be available at both the client and server side) you can set uploadpack.allowReachableSHA1InWant=true
on the server side to enable fetching of specific SHA1s:
git init
git remote add origin <url>
git fetch --depth 1 origin <sha1>
git checkout FETCH_HEAD
Note that I did not find a syntax to do this with git clone
directly.