Van Gaal's defensive options are limited after injured trio Phil Jones, Jonny Evans and Chris Smalling were ruled out of Saturday's Premier League fixture against West Ham.
Teenage sensation Tyler Blackett will also miss the match due to suspension, paving the way for Paddy McNair and reserve-team captain Tom Thorpe to be drafted in.
Many expected United to invest heavily in defenders following the departures of Nemanja Vidic, Rio Ferdinand and Patrice Evra.
While Luke Shaw and Marcos Rojo arrived, proposed moves for Thomas Vermaelen and Mats Hummels never materialised.
But do not expect Van Gaal to splash the cash for the sake of it when the transfer window reopens in January.
"My concern is never the age or the experience. My concern is the profile. You have to fit the profile," Van Gaal told reporters.
"I don't want to buy players who are not fitting the profile.
"There are a lot of defenders in this world but I don't want to buy any defender, I want to buy defenders who are fitting in the profile. That's what I'm like and age is not so important.
"I played with the Dutch national team, for instance with Bruno Martins Indi and Stefan de Vrij who were 22.
"They had never played in the Premier League or never played abroad. Now they are both abroad because of the World Cup [both left Feyenoord after Brazil with Martins Indi moving to Porto and De Vrij joining Lazio].
"I also played with Ron Vlaar of Aston Villa. That was my defence. And we did it very well in the world championship."
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