On another thread is a suggestion that you make metal blades and screw / glue them onto the hub. I tried that this weekend, expecting the worst (inadequate access, inability to get a decent fit etc) - but it was surprisingly easy. I made 5 sheetmetal blades (replacing the 10 that were there originally), each with a 1/3" tab; used the original stubs as guides; and used 2 sheetmetal screws and epoxy to put them on. The seem secure and survived WOT tests. The only surprise is the fan hub isn't a solid piece, but rather is only 1/8" or so thick where it connects to the blades. Notwithstanding it seemed to hold the screws ok.
I was disappointed that I broke the fan in the first place as I had installed the Brotek rear plate - but the determined stick found its way up there anyway and in a nanosecond the damage was done.