Arsène Wenger has instructed Arsenal's scouting department to explore short-term signings as the manager considers securing a quick fix to bolster his attacking ranks after losing Theo Walcott for the remainder of the season.

The management and scouting staff have discussed the possibility of adding a forward to their options since scans confirmed Walcott will be out for at least six months after suffering cruciate knee ligament damage late on in Saturday's FA Cup victory over Tottenham Hotspur. There is an acceptance, however, that the club will struggle to secure any of their primary forward targets before next summer at the earliest with those players' employers either involved in European competition, embroiled in title pursuits or simply reluctant to sell mid-season.

There is interest in Diego Costa at Atlético Madrid and Jackson Martínez at Porto, as well as Real Madrid's Karim Benzema and the Bayern Munich forward Mario Mandzukic, whose position at the Allianz Arena will be threatened next summer once Robert Lewandowski completes his free transfer from Borussia Dortmund. Domestically, Wenger has also considered the merits of the Manchester City forward Edin Dzeko, though any bids for such candidates would prove fruitless in January.

The manager has conceded that prices are inflated in the winter window and would be reluctant to pay more than Arsenal's valuation for such talent. Instead, players such as Real Madrid's Álvaro Morata, the 21-year-old who has been somewhat underused at the Bernabéu this term, will again be scrutinised while soundings are taken from possible recruits in Russia where some clubs, most notably Anzhi Makhachkala, find themselves under financial pressure to sell.

Lille's former Chelsea striker Salomon Kalou has also come under consideration with the player having made clear his desire to return to England, albeit he had envisaged making that move in the summer. Yet even a short-term deal would be progressed only if Wenger determines that the incoming player would hit the ground running as his team attempt to secure their first Premier League title since 2004.

The manager remains relatively relaxed about the pursuit given that he generally considers Walcott as a wide player rather than a central striker, despite the forward's prolific bursts of form when given opportunities through the middle over recent seasons.

Arsenal have cover in attacking midfield, not least with Alex Oxlade-Chamberlain back in full training after cruciate ligament problems and due to play in the under-21s game against Fulham on Thursday. He has not featured since the opening day of the season and, should all progress smoothly, could be in line for a place on the bench against Fulham in the Premier League on 18 January.

Wenger would have been more vexed had his first-choice striker, Olivier Giroud, broken down. Yet the France forward has recovered from an ankle injury and recent illness, and Nicklas Bendtner is expected back from his ankle complaint within a month. With January offering a relatively gentle fixture schedule, certainly compared with other months, the management may determine the better option would be to plough on with what they have if no short-term addition seems suitable.

There was sympathy for Walcott from the England manager, Roy Hodgson, on Tuesday as the 24-year-old faced up to missing the World Cup finals in Brazil. He will undergo surgery on his left knee next week before starting his lengthy rehabilitation. "I spoke with Theo and just wanted to express my disappointment to him," Hodgson said. "It is a blow for him personally and for both Arsenal and England.

"We had quite a lengthy conversation and it is such a shame that we have lost a player of his calibre for the World Cup. He has been incredibly unfortunate and we wish him a speedy recovery. Having worked with him for two years as England manager I know the character he has, and I know he will come back even stronger from this setback."