The pawls with the red arrows are what hold the console to the roof, they clip into rectangular slots in the roof reinforcements. The black parts are metal pawls, they slide over plastic tongues on the console posts. If those tongues are broken off (which is how they usually fail), there's no good way to to fix it. When they do break, about 95% of the time it's from careless installation. What usually happens is that the pawls get pulled loose from the tongues and remain in the roof when the console is pulled down for service, then they don't line up properly on reinstallation and get bent over and break. The way to prevent that is to remove the pawls from the roof with a needlenose pliers, then reinstall them on the tongues before trying to remount the console.
However, that replacement price is ridiculous. List price for B17 Sentra consoles is $240~$450. They're $160~$320 online, and good used ones on eBay are under $100. Installation is a five minute job even if the old pawls need to be extracted from the roof. So $900 is a replete hose job.