Window Motor Coupler - Alternate Materials?

[Team4014]

We've been trying to find out if the window motor couplers (here on Andymark; it looks like this, but has 6 holes around the perimeter, and came in the kit of parts - the PN is Denso-6) are available in any material other than plastic, and if they are, where to buy them. We're trying to get them in aluminum or steel, and we're hoping that we can order them online rather than having them custom made at a metal shop (we don't have the right equipment).

If anyone knows where we could buy these in aluminum or steel, please reply to this thread. Thank you!