Where to buy 1 5/8 feeder legs

I'm building a couple of tripod feeders and am looking for somewhere in DFW to buy 16ft long 1 5/8" OD feeder legs.
Home Depot and Lowe's only carry 8 or 10ft lengths for fencing.
Would prefer thicker gauge steel tubing over galvanized fence posts.
Does anyone know where I can pick some up?

I bought mine from a place that sells water well parts. When the thread gets damaged they can't sell it as new.

Discount Metals in Saginaw is where I get my 17' legs.

You might find tube that long at a real fence company.

I can get the 1 5/8" galv. up to 24' in length and up to sch. 40 in thickness. I'm located in Mesquite, just give me a shout and I can get you a price.

Any metal supply should have it.

Might also call salvage yards.

There is a used/seconds steel yard on Singleton in Dallas that should have it. I believe it is Liberty Metals or something like that.

Thank you everyone for all the leads.
I'll follow up here once I've got them.

I bought mine at Fulton Metal on 377 in Denton. Buy 20' pieces and they will cut them to length on the spot.