If you've made 10 it's easier than if you only make one.
If you look at it, it looks like some mesh material inside of a piece of rubber moulding.
If you want to make, start looking for the materials and go for it.
No one can tell what your time is worth.
2004 E60 530is, Delivered 12/12/03, TiSilver/LGrey, PP, SP,PS, PDC, ACC, FRS, Step, Xenons, clear bra, body colored rear inserts. (Retired, 1983 henna red 320is)
2004 Corvette Z06 Commemorative Edition