Shane Lowry made his first appearance for the O's, who had the majority of possession but could not find a breakthrough.
In a match of few chances, Gateshead goalkeeper Adam Bartlett did well to keep out Marvin Bartley's fine strike in the second half.
"It was a good workout and its been a really good week up here," Slade told the club's official website.
"I'm pleased with how we are shaping up."
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