That is small alright looks like a TD .010 would be the easy choice for fit.
I wonder if anyone has tried the TD .020. A Pee Wee is a bit heavy due to
the back plate run time is sub 2 mins needle settings vary, with a stock prop
19.8 to 20.5k static has been reached. I have managed 25k ish with lower weight
smaller dia. 3P props good numbers for a reed valve engine. 3.7 x 3E