I've never seen the backside of a re-produced one, but they are most likely like the originals with sheet metal and studs. You may be able to use some clips that would work but I have no idea which ones. You may want to try to make some of your own.
I replaced it on mine with a nos from eBay years ago & still have the stone damaged original. I had a look & I think it would be very challenging to reproduce the mounting brackets unless you're shed is very well equipped.
The outer 2 wouldn't be so hard but the inner 2 are tapered and have a bend with a ledge on one side along the complete length where it locks into the moulding. Best bet would be to find one & recover the mounts from it & use them in yours.
The taper would also make it very difficult to fit individual clips, they'd all need to be varying widths to compensate, but you'd also lose the interlock between the moulding & the mounts along the whole length of the moulding, which would likely make the moulding feel loose in some spots when it's fitted to the car.