Non A/C Blower Wheel help

I think i spend more time lurking than posting anything. I'm in the process of putting a 440 into my 74 duster. I changed the blower motor on the heater (non A/C) to the shorter PM360 motor, (this still doesn't quite clear the valve cover so I think I will recess it in another inch or so into the heater for clearance) In the process of disaseembling the heater I cracked the old and brittle plastic blower fan. does anyone now a source where i can get a replacement - the No's on it are Torin GA-404-212-1 2837 679 90264 4 I understand there is also a metal fan - No idea which is better so would appreciate any help

I did wonder about trying to use a blower wheel that would fit over the recessed motor so that it wouldn't intrude further into the heater box
thoughts?