The veteran striker had been a major doubt after falling ill on Friday night but he recovered to help seal an eighth straight win and Slade could not praise him enough.
"Kevin had been sick all night and all morning and we nearly didn't play him," said Slade. "But he wanted to go out and make a go of it and he scored two goals.
"You'll have seen from his performance that he's usually much more lively than that, but he couldn't raise a gallop at times.
"His concentration in front of goal to get us the two goals was fantastic, so all the praise in the world for what he's done.
"It was really pleasing. It was a really honest and professional performance. We knew they'd close us down quickly and put us under pressure, but we were so prepared for it. It was great the way it turned out.
"The players certainly know their jobs and they know each other's jobs. From that point of view we're looking well oiled at the minute and we've just got to keep that momentum going."
Lisbie had opened the scoring with Orient's first shot on target, holding off Matt Doherty to fire powerfully into the bottom corner.
Orient doubled their advantage when Lisbie poked home Lee Cook's corner.
Doherty missed a great chance for Bury, heading wide from Steve Schumacher's corner, and Allsopp saved a Bishop header from point-blank range.