currently there is no official source. A 1.0.x phar should normally be available from https://jenkins.pmmp.io, but the hosting provider seems to think he has to delete everything, so I quickly made a phar for you (commit b22232730ef6fa50f1cce2e3c5fe488118d01df3;branch mcpe-1.0). It is attached. PLEASE NOTE: DO NEVER TRUST unofficial phars. Even this one I just gave you. I didn't do anything to it, but you could never now. DO NEVER RUN with admin rights.