https://www.vice.com/en/article/dy7kbq/palmer-luckey-made-a-vr-headset-that-kills-the-user-if-they-die-in-the-game
“The good news is that we are halfway to making a true NerveGear. The bad news is that so far, I have only figured out the half that kills you,”
I'm not sure it's possible to beat Contra without the extra lives cheat code.
There are spots where you can lay down, keep shooting, and build up points and extra lives from those points from enemy respawns.