Those chairs are super cute. I like the suggestion of white, and I also love terra cotta with that shade of blue.

Regarding making your own seat out of plywood, padding, and fabric: Don't forget to top it off with a clear, plastic material (sold at JoAnn Fabrics) if the furniture is going to be kept outside. Otherwise the rain will rot the wood and the fabric will get moldy!

clear acrylic.

Ooo acrylic, that's a fantastic idea, david, and paired with Maxwell's suggestion of white cushions! I'd probably just bring the them in before lining them with plastic though, unless i can find weather-proof ones. Would I need anything special to cut solid acrylic and can I just get that at a bigbox home improvement store or someplace more specialized?

If you are interested in waterproof cushions, contact your local marine supply store. They could probably give you the name of someone who makes cushions for boats.

I've seen waterproof cushions for outdoor furniture at Home Depot.

You can buy marine vinyl at any regular fabric store. I've covered cushions with it and left my chairs out in the rain with no problems. And if you fully upholster the seat - rather than placing a separate cushion on the plywood - you won't have trouble with the weather affecting that either.

actually i have this same chair i found on the street.
mine was painted black but underneath was a very pale yellow. I am jealous you have the whole set.
mine had the cushion which had a wood base and the ever lovely brown vinyl w/ piping on it.
I use it for inside to have an orange/brown oxford type fabric w/ leather piping.
the contrast piping adds a nice pop.

What David said about acrylic, except look for a product called Lexan, which is like acrylic, but doesn't crack. Polycarbonates, in general, are stronger than acrylic. For cutting either, you can do it with a standard jig or scroll saw. Stapling fabric, on the other hand, is going to be not such an option. But, you can make removable cushions easily.

Speaking of which, make sure you drill holes in the seats to allow drainage, regardless of what material you make them of.

For foam, you want a product called Dri-Fast, which you can order from IR specialty foams. It's specifically designed for outdoor furniture to allow water to drain through. It's possible that you can find a closer location.

I really like the Scalamandre outdoor fabrics, esp Castaway:
<a>http://visualaccess.scalamandre.com/wwiz.asp?wwizmstr=O

I have a similar set which has plywood seats covered with fabric (someday I'll redo them in Castaway) but I'm not sure the wood works if you want to leave them outside always (as someone above pointed out: rot will be a problem).

Here is the (non broken) link again: http://visualaccess.scalamandre.com/wwiz.asp?wwizmstr=OE.SKU&sku=16335-004

Try using an outdoor fabric such as Sunbrella, which you can get off the roll in some Jo-Ann's stores and which you can get off the Internet from many places. It is treated with a water-repellant treatment that helps keep the pillows from becoming a sodden mess, and it resists dirt and sun.

Ballard Designs makes cushions for outdoor use in a wide range of shapes. If you get the Lexan, etc. cut you can just put the cushions on top!

I have a sewing machine, but figured between the Sunbrella fabric and waterproof foam (not to mention zippers!), it's not much more to have custom outdoor cushions made. I used http://www.cushionsource.com/ not particulary chic or cheap, but well-made. Here are mine in action: http://flickr.com/photos/marstin/894867929/