HP25C repair, help needed

[burkhard]

I think in the US, the equivalent would be Elmer's, specifically "Elmer's Glue-All"

Elmer's Glue-All

Normally I think of this and other PVA glues as more of a craft glue for porous material like paper, felt, cardboard, wood, &c.
But maybe this is a good application (as long as it doesn't eventually release on its own or from the calculator suffering a bump)

Keep us posted how it all works!