If you can find three 1/8" close nipples (no, I'm not making that up) and two 1/8" straight couplings to match, and two 1/4" flare nuts, and a bit over a foot of 1/4" brass or steel tubing, and some more brass or steel tubing that fits snug over the 1/4" stuff, and a small tubing/pipe cutting tool, you're most of the way there. These are the parts I got from my local hardware store:
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You
should be able to find something quite close to that -- standard or metric -- locally. Here's how they line up to the originals (I used the laser caliper dots to scale the picture up to 1:1):
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I cut one of the nipples in half and screwed those bits into the "downstream" ends of the two couplers, cut and ground to the right length, glued a bit of the larger tubing over the 1/4" stuff, and that gives a nice enough fit for the epoxy to secure the whole thing to the tubing once you're done. The other two nipples get shortened a bit -- as you can see from the last picture above, they're a bit too long out of the pack. Once you've got it all the right length and glued together, you can paint them in an appropriate steel/aluminum/whatever metallic finish.
Useful?
[ETA: If you
can't find this stuff locally, or anything equivalent/better, PM me and we can sort out having me snag some and send it to you.]
--Jonah