Re the Tygon.. yes, thats a good point and replace it with silicon. But it works fine for the few flights I've had with it like this. Its not finalized design, as (for one) you point out there tube is kept on by friction only.. Solution seems to work, but doubt it will in the long run. -WIP..
Regarding the spring, it may be exaggerated by the angle of the photo, but the two blade spring is soft. Will double check when I go and look later.
The Ahi you can get from Europe.. I.e a shop here in Norway:
https://www.rc-modellflysport.no/products/dream-flight-ahi -I am sure they ship one to Alaska..
(
-If we get over the Corona issues any time soon, I can get some of my colleagues that fly between Norway and US to bring one across.. (Can revisit that in due time.. ))