springy / hard elastic fillament reccommendations

Hi, I'm searching for a fillament with a similar hardness/resistance to PLA but which doesn't plasticly deform when bent for longer periods of time.

This is for a wearable, specificly the c3cat cat ears. I printed mine out of PLA but they got too loose after 2 days of wearing.

I already got reccommended TPU 100A, but I worry that it's too soft.

Thankies :3