Which part of it broke? I'm guessing the handle tore off the mounts? Maybe look for something that looks like a dogbone handle but is made from metal with rubber on the outside. Or you can fit one like this, like what they have on Marshalls / Hiwatts, they never break:

http://www.mojotone.com/amp-parts/amplifier-handles/Hiwatt-Style-Strap-Handle-with-Chrome-End-Caps-w-Hardware#.VjHuOIQmWkg