SFTP module cannot request directory listing, does anyone have a good workaround?

I have been using the SFTP module in a Scheduled Script to successfully to upload files to a third party SFTP server, this works well. But I also need to download files and the problem is that these files have a timestamp in the file name. Because its a third party I can't dictate the file name and the Netsuite SFTP module only seems to be able to download a file if you know the name. In other words there is no feature to request a directory listing on the remote server and hence determine what the file name is