Any level way below base Vegeta seems fine to me. Since base Vegeta was in between 18/17 and 16 imo, Pui Pui should be way below 16 and likely 17 and 18 too. Since he's also very irrelevant, I don't think he needs to be even relevant to SSJ Namek Goku or Freeza... I've him at 20,000,000 or so.
I've base kid Trunks at 450,000,000 (= 18), and he couldn't handle a 150x G while in base, showing that an unused being couldn't handle a 150 while being 450,000,000 (my numbers yeah). But I think he was already kinda close to breaking that. By that logic, a 30,000,000 untrained warrior could have the same trouble dealing with a 10x G as Trunks, so a trained in gravity warrior, Pui Pui (20,000,000) could defeat a stronger warrior under those circumstances (only, base Vegeta was way stronger). The hole in that is that if Pui Pui had an accurate knowledge on Vegeta's prowess, he should know he'd break into the 10G even while being unused to it (as he was >>> base Trunks who could already, even struggling, walk in a 150G)... But maybe a) Pui Pui sucks and couldn't tell Vegeta's strength accurately as he maybe couldn't even process things amidst his confusion in being spanked like a doll, or he just knew that an untrained warrior couldn't withstand a 10G, he just dien't take into account that when a certain threshold was reached, that could be achieved.
Btw those are just some lousy estimation. Pui Pui can be whatever.