I got mine at the feed store it is a 60w. Here is a link to the one that I got. I hope this helps.
http://lllreptile.com/store/catalog/reptile-supplies/heat-bulbs-night-heat-bulbs-ceramic-bulbs/-/zoo-med-60-watt-red-bulb/
I was having the same problem so I put in a red light and it has stopped the pecking. My chicks were pecking at the eyes. I hope this helps you!
Rebecca