Side mount spares-Anyone make their own?

I have the opportunity to get a late '30s Buick that has front fender mount spares but they're missing. With all of the very talented and resourceful people on this board I was just wondering if anyone made their own. I am trying to think of what common items I could use to make a pair that look close to the originals. From what I have found on the net the side mount spare are awful hard to find. I have found a set on the net but they want big $$, more than I paying for the car.

I was thinking maybe I could use round trailer or motorcycle fenders for the outside of the covers but I can't think of anything to use for the inner parts.

 

how about a wheel cover off a 80s conversion van then weld a hubcap in the middle (maybe like a moon) smooth the fabrication and paint.

 

I didn't even think about a van spare tire cover, good idea.