Tabor pipe - help?

PFH has put together some wonderful models of tabor pipes which I love. However, the two that I've printed (a D and G pipe) are both about a semitone flat.

Does anyone know enough about the harmonics of wind instruments like this to know how much I should increase the size of the print by to get them in tune?

Additional context: My 3d printed D pipe is 26.7cm from the window to the foot of the pipe, whereas my manufactured D pipe (which is in tune) is 27cm from the window to the foot - a 0.98% difference, apparently.

My G pipe is about 41.1cm from window to foot. Scaling it up by the difference between the D pipes would give me a length from window to foot of 45.2cm... however, the hole placement is also different between the two pipes, so I don't know if simply scaling it up would suffice. Argh!

https://preview.redd.it/u0r0qlp4x65d1.jpg?width=1537&format=pjpg&auto=webp&s=1fd758faf984de7afa0509771db693387b01ffdd