Ric Flair ain't just not dead ... The Nature Boy's doing so well, he could mount a WWE comeback -- so says Brooke Hogan, who just talked to Ric on a trip to see her dad. 

Hulk Hogan's daughter told us Naitch was so fired up (WOOOOO!!) ... she wouldn't put it past him to return to the ring after he completes his recovery.

"He sounded like he was all full of piss and vinegar," Brooke told TMZ Sports.

"Guys like Ric are pretty indestructible ... they keep comin' back."

Flair's buddy, Stone Cold Steve Austin, basically said the same thing ... so don't rule it out.

As for Hulk ... Brooke says he's looking great at 64 -- and told us the one thing that would 100% get him to throw down again.

I'M BACK!