I recently went through the process of trying to find someone to make cushions at a reasonable price. It was nuts! Nothing even came close to fitting into my budget. (Admittedly, my budget was very small.)

I wound up making DIY cushions that worked wonderfully. You can buy high density foam, dacron and foam adhesive from a number of different places. I recommend either Canal Plastics Center (Chinatown) or Barth-Tex Upholstery Supply (Ditmus Park, Bklyn). There are number of tutorials, including videos, online for making your own cushions. Try searching DIY Upholstery Supply on YouTube.

Looks from the photo like the cushions are rectangular. If not, it's still very do-able, you'll just need one more tool-- an electric turkey carver. (weird but true).

If you're looking for slipcovers too, this advice doesn't really apply. But for replacement cushions, I swear it's an easy project and well worth the money saved!

About 2 years ago I got the foam replaced in my MCM daybed by Foam Center Inc on 180 Bay Ridge Avenue Brooklyn NY 11220. The name of the person who does the work is Debra and her number is 718.680.8550. I would have had the full cushions redone if I had been able to decide on a fabric. When I do finally decide on a fabric I will go back to her though.

I found 2 of these exact chairs at a yard sale. Snatched them up for $8 a piece.
I didn't realize the work that would go into finding cushions or having cushions made for them. I lived near the Navy Yard at the time & went to this crappy little furniture fixings place on Myrtle Ave. The guy wanted $250 to make me 2 cushions (just the cushions, no covers). If that were the only issue, I would have kept my lovely finds but the worst part was finding out how to rebuild the straps that held up the cushions. It was a sad day when I left them in my building basement. Sometimes a bargain isn't really a bargain. Good luck with yours. It's a beautiful chair.

There are actually some great suggestions right here on Apartment Therapy from a conversation in June. You may want to check out some of their suggestions here: http://www.apartmenttherapy.com/source-for-custom-chair-cushio-149799

Do a Google search for MATTHEW HALY in New York City. He does this work. I don't know where in NYC, you'll have to check it out.
Georgia

I am an upholsterer, and have done 100's of these danish modern chairs. They are fantastic chairs for NYC apartments. 250.00 for the set of cushions is a great price, if the covers are included. I do have some photos of this chair with new cushions on my web site, Beatriceupholsterynyc.com. Those foam suggestions from trumystique were very good, although if I bought foam from them, I would go out of business. Foam isnt cheap, and having a biz in NYC is not also, remember, mark ups are where a profit is made.