United host La Real leading the round 32 tie 4-0 on aggregate.
Solskjaer confirmed Galbraith could be involved after the young Northern Ireland midfielder was added to the B list for the Europa League.
“Galbraith will be with us," he said.
“Hannibal (Mejbri) unfortunately injured his shoulder in the Reserves so he'll be out for a few weeks. He was just on his way into the squad and training with us but that's football. He'll come back stronger, I am sure, and he knows he's not far away."