The sealant is not there to hold the cowl in place. Although it can if the clips are broken.
It's just EPT sealer. Ethylene - propylene terpolymer. You might be able to get it from a Nissan dealer. If not, it looks like Honda sells it.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |