Space Button No Longer Pops Back Up

The space bar felt like it was stuck, so I followed instructions to remove it. I cleaned it, but there was no obvious ‘spring mechanism’. When I reassembled the space bar, there was not a change.

I took it back apart and it appears that the bump or ‘wart’ in the middle which is part of a ‘mat’ is supposed to supply the ‘spring’ and this rubber-like bump is torn.

Am I correct that is the issue? Can I replace the mat that has that bump?