Where would you find one? RockAuto doesn’t, nor AutoZone.
eBay has them.
RockAuto’s tag line of “all the parts you’ll ever need” is BS.
If @jtsanders not posted an Ebay link I’d have said “fabricate one”. Expecting to find parts for a 33 year old car is very problematic as you get beyond brake pads, starters or alternators.
I looked on eBay first. If I specify 240SX they don’t have the EGR line. The part you reference says it’s for the 200. Are they the same? Can one eyeball it? The pictures are different shapes. I notice it’s in Albuquerque.
That’s been considered. I expect that to be expensive.
I’ve had no problem for my '87 Toyota.
I did a web search for your application and there were many in the shopping section. I chose one with a lower price and clicked on it. The webpage told me to confirm the application and I input year, make, and model, then it confirmed that two were available.
Poke around here:
https://www.partsgeek.com/ymm/1992/nissan/240sx.html?search=egr+tube
Your best bet is to check around a 240SX forum, someone probably has one in their garage they would sell you…
Fun little cars, very cool…