Vintage cabinets

Hello everyone. We recently just bought a home and it came with some furniture that I am interested in knowing more about.

First off I have two identical cabinet/credenza pieces in excellent condition. I do know that these pieces were made by George K. Johnson who is the former owner of Johnson Bros. Cabinet Works with his brother Douglas. That's about all I know of these pieces. They weigh a ton built of solid wood (walnut I believe) a couple of minor scuffs and nothing more. 

Could anyone help me out with a fair estimate of these pieces?

Thanks! Sara

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