This should be going in the ACNL subforum, you'd get more replies there.
Anyway, to get golden furniture from Cyrus, you need 3 gold ores and and 10,000 bells. You can get the gold ore pieces by smashing the breakable rock, sometimes you get those though they're not the most common. Then he'll make the furniture for you. I don't think you can select which piece of furniture you'll get, it's just a random one from the gold series.