I just want to know if it's possible to get OMM 1.3 or lower

No it's permanently deleted u need to ask some1 to send file through gmail

Damn

it's possible via github

https://github.com/PeachyPeachSM64/sm64ex-omm/commits/coop/

Thank you

its on the dx mods site as well

no, the coopdxmods haves the link to newest version of omm