You have a tiny chance to find one in Dragon's Lair.
Dragon's Den + Super Rod = Dragonair
you can probably find it on Ebay
level 55
In Route 44.
You can find one on Route 44.
pokemon heart gold
in golden rod city
The tower
on route 44 you will find him
If you can trade Pokemon from crystal version to gold version my guess is yes
i used ampharos, typhlosion, ho-oh, gyrados, kadabra, and dragonair
Level 30 to Dragonair. See links.