Beefing up the Baboon, But just a Bit

[Ogun]

I am looking for a small wildshape form that has hands, that can also act as a HP buffer for a spore druid
Baboon would be a fun but it only has 3 HP and a CR of 0.
Is there an established way to improve a monster, and measure the improvements?
Is there a generic 1/4 CR beast that could be used as an apelike transformation?
I've found a 3rd party Howler Baboon that would fit nicely, but it is 3rd party, so maybe it's too good:

https://www.5esrd.com/database/creature/baboon-howler/


While I'm thinking about it, does Symbiotic Entity's extra 1d6 necrotic damage work with natural attacks, post Mordenkainen's Monsters of the Multiverse?

[Sigreid]

There are quite a few ways to get temporary hitpoints that you can look into. Then you can go with the regular baboon and still be a bit better.

[Ogun]

Symbiotic Entity gives temporary HP, I was hoping to stack that with wildshape HP and be super stupid beefy.
As it stands, baboon HP is crappy.

[Guy Lombard-O]

I mean, just homebrew a "greater baboon" at the CR level you want, give it appropriate HP and increase the damage die by one, and call it a day?

[nickl_2000]

Start with the Base Baboon and adjust until you hit the CR you want.

[Ogun]

Nickl 2000, that seems perfect, thank you!