AFC Bournemouth have signed Christian Atsu from Chelsea on a season-long loan deal.
Midfielder Miguel Pallardo has signed a new one-year deal with newly-promoted Hearts while Danny Wilson leaves.
Losing forward Kevin Mirallas and defender Tony Hibbert to injury for "a few weeks", and the club's current hold on fourth place, has not changed the Scot's view about the forthcoming window.
Everton have habitually sold in order to buy, but Moyes stressed that would not be the case in January, despite speculation suggesting he was willing to offload defender John Heitinga in order to raise money to buy Paris St Germain striker Kevin Gameiro, Toulouse youngster Wissam Ben Yedder and bring back Manchester City defender Joleon Lescott on loan.
"I'd like to (strengthen), but we know I've got a very small amount I could do anything with and I don't think it will probably be enough to make a difference in what we would want to bring in," he said.
"We will probably look and see if there is anything out there but I don't think the situation with Mirallas and Hibbo would change that.
"We wouldn't be letting anyone go, but we would like to add to it if we can, but we can only do that if the players were available and it was the right deal for us."
Losing Mirallas, arguably Everton's most impressive attacking player this season, for an extended spell is a significant blow to the Toffees.
The Belgium international only made his comeback from a hamstring injury in last weekend's win over Tottenham after missing four matches but lasted just 45 minutes.
Even in that time he was Everton's best player and Moyes knows his absence considerably weakens his side.
"It looks like we'll lose Kevin for a few weeks," said Moyes.
"It's a really big blow, anyone who watched the game last week can see that.
"His hamstring isn't just right so it looks like we'll have to take more time over it so it will probably keep him out for a while.
"We thought we had managed it because it was quite a mild hamstring injury which we gave extra time because I was expecting him to be available for the midweek Arsenal game.
"I then didn't use him in the Manchester City game in the hope he would be right for the Tottenham game so we gave him extra days to make sure it was right.
"We now will have to take even more time for us unfortunately and it will be a big miss for us because he gives us a different attacking dimension from what we have and he'll be a loss.
"Tony Hibbert has a recurrence of his calf injury so he is going to have an operation on Monday which will keep him out for a while."
Everton will bid to maintain their fourth place at Stoke on Saturday, where goalkeeper Tim Howard is expected to make his 200th consecutive Barclays Premier League appearance.
The United States international has been an ever-present for more than five years, with the last time Everton played a league match without him coming on 23 September 2007 when Stefan Wessels deputised against Aston Villa.
"He has been a great buy for us. When I was losing Nigel Martyn I was saying 'Where am I going to get anyone as reliable, consistent with the same personality?"' added Moyes.
"I've been very fortunate I've picked one that is good in all ways. He has been a great goalkeeper, he is great to have around and is a great ambassador for Everton.
"He is fit, he is good, his work-rate is excellent and we are really pleased to have him.
"When you leave Manchester United to come here, a lot can depend on how you react and he tried to rebuild himself and show how good a goalkeeper he was and I think he has proved that."