Hi all, on 1 of my carbs (front left sitting on bike) the manifold has come apart from the rubber connecting to the carb. I've searched and these are discontinued

Tried ebay but they all look knackered and the only NOS is for the rear carbs,

How can I attach it back without getting any air leaks? I was thinking using hot glue and pressing it back into place. Would this work or does anyone have any better suggestions?
Many Thanks.