I suspect not. The mechanical design of those things is NOT trivial, nor is the incorporation of the pin into the chainring easy (especially under conditions of use). Also, the design must be made for both chainrings - one doesn't add pins to a ring without knowledge of the oother ring(s).

Even if you could get them, to install them you'd have to have some pretty sophisticated milling and drilling and press and measurement equipment. I don't think adding the pins is practical, compared to just buying the pre-made chainring set.

But perhaps the OP owns a machine shop....