The French coach has left Gorka Elustondo and David Zurutuza out of his squad for the match and although the two players have been recovering from injury, Montanier insisted his team would not be affected by their absence.
"The strength of Real Sociedad is that we have a versatile squad that is well prepared to compete," he said during a press conference on Friday.
"We can change two, three or four players from the starting line-up and still maintain our effectiveness. I have everyone available and it's not easy to choose a squad for the game."
If the Basques beat Levante on Sunday, it will be the first time they have recorded three wins in a row this season, a milestone which Montanier has called "a challenge".
"It is difficult but not impossible," he said.
"We are going to try and do it but we face a problem called Levante, who will come here keen to get points and go further up the league table.
"They are a complete team that do everything well. They know how to defend and wait for teams to come to them, they play on the counter-attack and move the ball quickly.
"It's no coincidence that they've had two great seasons and beating them will be a challenge for us."
Levante go into Sunday's game off the back of their stunning 3-0 win in the first leg of their Europa League last-32 clash against Olympiacos on Thursday and captain Sergio Ballesteros has spoken of the importance of his team getting over the high of the game and getting a positive result against Real Sociedad.
Even though the Valencia side are 13 points clear of the relegation zone and among the teams fighting for a Europa League spot for next season, the centre-back stressed that the team are still prioritising remaining in La Liga above anything else.
"We have to adapt quickly [after the Olympiacos game] and think about the league," he told reporters.
"We want to guarantee survival as soon as possible so we can be relaxed. We are facing a team that are above us and very strong at home. We'll have to take the game very seriously if we are to win there."
Ballesteros explained that his team's main priority against Montanier's side was to keep a clean sheet.
"We've gone behind early in games and had to try and come from behind," he said. "Our aim is to try and not concede goals because we are capable of scoring in almost every stadium we play in."
Ballesteros missed the Olympiacos game but declared he is fit to play tomorrow. However, Nabil El Zhar is expected to miss the game with a sprained knee.