I will ship these from germany. I'm in the US a lot though so i might be able to import some directly at some point. if someone wants bigger quantities i am sure we can arrange for shipping directly from the manufacturer.
As for the encoders, the board fits and supports all types of Bourns PEC11 and PEC12 series encoders, with and without detend and with and without built in switch. each 4x board uses 2 HC165 shift registers, 2 pins for each encoder, one for the optional switch, one unused, repeat.
the encoders and the input/output connectors are about the only parts you have to pick, buy and solder yourself, as they are too much of a personal choice.
if needed i guess i could do these super easy soldering jobs for people, in very small quantities.
got the prototypes running perfectly nice on both arduino and STM32F4 midibox, will look into axoloti objects tomorrow or early next week.
edit: @johannes old SPI ws2812 project works like a charm and the first board of 4 LED rings is looking great on native axoloti control! will start writing some convenient objects once i understood johannes driver/adressing scheme...