You should be able to find one at Home Depot, Lowes or maybe even a large hardware store around your home. HPS and MH bulbs are used in overhead security/flood lights and you can buy the replacement bulbs.
As for the fuzz it all depends. Ordering one or two bulbs, or even a home indoor growing system isn't illegal as it can be used for other household plants. Ordering from on-line hydroponic stores that cater directly to marijuana growers is a different story and should only be done where it is legal. It is also not a great idea to order to complete grow kits or all of the materials at once to the house your gonna grow in. Buying enough equipment, multiple systems, to start a "grow house" along with an increase in energy usage over the next few weeks will definitely tip off the cops.