Brownell's has 1911 DD Mahogany Checkered grips for $18 + $5.35 shipping = $23.35.
http://www.brownells.com/.aspx/pid=9562/Product/1911_AUTO_MAHOGANY_GRIPS
http://www.brownells.com/.aspx/pid=9562/Product/1911_AUTO_MAHOGANY_GRIPS