How could I imitate this?

Styrene tube, with copper wire wrapped around said tube and shrouded with heat shrink tubing. You can insert a solid, metal rod (aluminum) so it will hold it's shape...

the straw is too big in diameter so cut a section out of it reducing the diameter by a mm or 2 then reglue it seam downso it is not seen

If you look around, I think you might find a straw that is pretty close to the right size. My wife bought pack of cheap bendy straws at the grocery recently, and they were quite small. If I can find one, I'll measure it.

you could also take a large piece of styrene rod and use a scriber to cut in lines, then attach that to a smaller piece of rod, though, some of the suggestions before seem simpler? Good luck.

Juice box straws are small... I think i like snarpeezel's method better though

Hmmm, if I recall correctly I think there was some flex hose you could buy in 1/24. Use for air ducts in NASCAR stuff, etc. If I remember right I got it from TNT hobbies. This was a few years back, not sure you can still get it now.