Overstock.com has a decent knockoff. $159 for 2 chairs...and they ship for $3.

Here's the chairs: http://www.overstock.com/Home-Garden/Ronnie-Wire-Base-White-Chairs-Set-of-2/3351572/product.html?rcmndsrc=2

They also have them with wood dowel bases.

Overstock has a pretty good plastic knockoff of the Eames eiffel base shell chair...
http://www.overstock.com/Home-Garden/Ronnie-Wire-Base-White-Chairs-Set-of-2/3351572/product.html

Have you tried Room and Board?
Their "Jake" chair is a Arne Jacobsen knock-off. $79 each
I believe they're headquartered in Minneapolis.
I bought a set of Jasper Morrison Air Chairs years ago --on sale.
Excellent customer service.

excited to see my question here...we went with the overstock (eames-look wooden dowel) chairs
http://1088churchill.blogspot.com/2011/08/new-on-herman-miller-eames-armchair-is.html
and so far are really happy with them

the Oh chair is great! We have 2 at our kitchen ikea tulip table. They are cheap and very comfortable.

we went to Room and Board and sat in the Jake chair--loved the style but didn't find them very comfortable. We really wanted the Eames but couldn't afford the $250 price tag.

AMAZON.COM Has Eames Eiffel chair knockoffs, and Panton chairs, affordable and usually free ship.

we liked the oh chair too, do you have it in white?

i'll second the oh chair. they're about $40 a pop. we got them instead of going for eames chairs and have not a thought to replace them after over 5 years. they're super cozy, durable and easy to clean... and stackable!

I just noticed that they're selling white eiffel chairs today on the Foundary, $180 for a pair that they say usually sells for $420. You have to sign up to see them (I think) but here's the link: http://shop.thefoundary.com/product_31811.html.

I love the Tolix Marais chair from DWR and it is great when they go on sale, but the gunmetal color is still $212 versus the original price of $250. Needing 4 side chairs and 2 arm chairs (which runs $275 original each) We're looking at thousands of dollars! What does everyone think of Industry West knock off of the Marais? Anybody purchased them? How do you like the quality? I was hoping if they are knock offs, at least they are made in USA, but I think they're made in India. We all know Tolix is Xavier Pauchard's and is made in France. Thanks!

I wonder what the delay is between questions getting posted. It seems like half the time the askers have moved on already. Are they too impatient or is AT really too slow?

lepidoptery-i posted my question about a month ago. We had a dining table and no chairs--couldn't wait very long to buy!

Which one did you end up getting, Julia? I feel guilty supporting the knock off manufacturers. I want stuff made here or the original designer benefitting, but they're just too expensive.

I also think the OH chair is amazing.

http://www.wayfair.com/Ameriwood-Industries-Bentwood-Round-Chair-in-Espresso-Set-of-2--3332196-AR1613.html

harl3y: we ended up buying from overstock. i felt guilty too, but i scoured for several days and didn't find any vintage sets we liked. We can't afford new Eames and wouldn't trust our kids in them if we could! here's the link: http://1088churchill.blogspot.com/2011/08/new-on-herman-miller-eames-armchair-is.html

Spinario in NE MPLS has lots of mid-century pieces. They're not cheap, but you can frequently get a good deal. spinariodesign.com.

Search PHM and Golden Age Design on CL. They're local furniture enthusiasts who post great finds in great condition.

The Saint Paul Retro Loop is also a good circuit of shops in the Mac-Groveland and University Ave neighborhoods. Google it for list of stores that are part of the "loop."

Room & Board outlet in Golden Valley. We are VERY fortunate here in the TC to have the outlet, which is open weekends only and has great pieces and incredible prices. A little scratch and dent, or special orders that were never picked up.

The TC has a great retro scene and I'm sure you'll be able to find something. Good luck and have fun!