I have seen steel pipe on craigslist too, so check there as well, sometimes guys are getting rid of stuff and you can get a bunch cheap.
One guy here in Reno was asking $70 bucks for 28 sections of 4 to 5 foot long 1.5" steel tube - I may see if I can grab some for my roll cage. being short may require a few extra welds, but, hey, at around $2.50 a piece it may be worth it.
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