Contrast between orb and square might be too much - not really simple, just geometric. Shows prints? Orb Knob - Modern Collection by Emtek
Emtek Stainless Steel Modern Round Door Knob, interior door handles, $132
The Ariel. Mid-Century Modern exterior door set. Three finishes available. Elegant circular simplicity.
available in brushed chrome, oil- rubbed bronze, and polished chrome 8.00 at rejuvenation.com
New entryway door knob? Mid century houses are tough to find replacements for! Z019082
Put this Hardware on the Ikea Cabinets. Saturn Cabinet Knob with Star Backplate Die-cast Zinc, Stamped Brass
Awesome address signs. Would look great back-lit.
Sure-Loc Door Hardware - Bergen Modern Round Knob with Square Rosette
period correct Eichler style door knob and hardware
Schlage orbit knob