How far are you planning to drive to the inspection station? Because even if an officer doesn't spot you, there's always a risk of a fine, and the longer you put it off, the greater the chance that your luck will run out eventually. A fine for an expired inspection is a real thing, and the amount depends on how long ago it expired, but either way it's going to suck.
In practice, a lot of people actually do drive around with expired inspections because checking the diagnostic card isn't the most common thing during a routine traffic stop. But that doesn't mean you're safe. I once went on a long trip with friends, and he completely forgot about his inspection. On the highway they pulled him over, checked his documents, and that was it - got fined to the max. His car looked perfect, but the officer just happened to decide to check the card. After that he started taking it more seriously.
The main thing is don't press your luck. If you've already decided to go to the inspection station, pick the shortest route, avoid traffic police checkpoints, and don't draw attention to yourself in any other way. And honestly, just go get it renewed, then you can stop worrying about it.