The "one arch piece" that's so cool! Wheres the Vader Aficinados to tell us what's the found part???
The part on the Speederbike is a grey PVC 32mm pipe clamp. I'm shure about the size, as the sizes above and below are way over or under what fits the short "arms" they are attached to, well at least on the Speeder....
You find em on ebay
The one on the Bobba blaster looks different to me. It seems to be a type that has some "ears" at the end(just where your red arrow points) of the rounded part to receive tubes.
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