Recently I acquired a nice pair of Ianbeam 650s. One of them has a speedring for a Chimera which I would love to make use of. However on the budget I'm operating with a Chimera softbox at $300-500+ isn't the most cost effective solution for me at the moment even though I love their quality. Are there any other brands of softbox that are compatible with my 4 point speed ring? Preferably something that wont melt and burst into flames with a 650-1000W lamp behind it. I've searched all over eBay and all I can seem to uncover are softboxes geared towards strobe use and not continuous lighting use. Any recommendations would be greatly appreciated!

The Photoflex NXT range are made for hot lights - cheaper than Chimera but not by a huge amount.

Cool Lights makes a decent soft box for the money. Only $100. It should fit the Ianbeam but I'd check the dimensions.