Bob,
you won't find the wing tube but HK has some nice 15 & 20cc gear that will work. The LG block is the Achilles heel of this airplane, so I got some 1mm CF plate, cut it as required & reinforced the gear block from the canopy side. It requires cutting open the first bay of covering under the canopy & drilling out new holes in the gear. I am sure you will figure it out
Ameyam