Posting a photo usually helps. What style are the chairs?

They are the same design as this http://www.steeldomus.com/img/b_a_plywood_low_chair_charles_eames.jpg, but are made of a different kind of wood

Here is a link that might be useful:

Since they produce these chairs currently there is a bit of controversy as to how much they are worth compared to a newly produced chair, just because they are older. There are a number of factors. If they are very early ones (1946) they may be more valuable compared to others later on in production. If they are an unusual wood they could be worth more. (I am not familiar with how many species they were produced in originally). Condition is also important unless it is a Very Early chair. MCM furniture does not take chips and wear as well as early American, for example.

There are also two versions of this chair, a dining chair and an lounge chair, that have slightly different dimensions. They currently retail for $630-1300 each depending upon the wood species.

On January 14, David Rago of Rago Arts is having a "No Reserve" auction and there are a number of these chairs among the lots. You may want to sign up for this auction just to see what they go for.
The ones that I saw at a glance were "Unmarked" which generally lowers value. The LCWs in his auction have an estimate of $200-300 for a c. 1950 Walnut. However, the current value of things like this are what people will pay for it. A no reserve auction means there is no lowest price they will take for these items. Yours are marked that would make a difference.

MCM is doing ok right now, value-wise. This auction house is reputable and he regularly appraises on Antiques Roadshow.

I would also follow them on eBay for another way of tracking: just look for Eames or LCW chairs.

You could also contact David Rago's firm for an appraisal. It is discussed on their website.

Here is a link that might be useful: David Rago.