You can always use the post ID to link to a page, like this:
http://yourdomain.tld/?p=1234
You can find out the Post ID right from the post overview screen. If you hover over the “Edit” or “Delete” link, you can see that the URL has a parameter post=. The number behind that is your page ID.
It could happen, that WordPress redirects your “post ID permalink” to the “real” version with the slug, but you are good to use the numeric one for linking.