I got your email from Paul. Re those questions you are interested, I would like to response as follows:

1) Yes, there is single-sided FR4 1.6mm 35um copper laminate on most of the double-sided laminate suppliers' products list. However, as single-sided FR4 is not popular when compare with double-sided FR4, laminate suppliers ask for hugh MOQ. In addition, the price difference between single-sided FR4 & double-sided FR4 is not big, say 10%. In order to escape from the big MOQ reqirement, PCB manufacturers start on double-sided & etch away one side of copper in case they need single-sided FR4.

2) Yes, FR4 is punchable for holes with diameter 0.8mm to 7mm & for outline profile. However, punched holes is not good for copper plate through as the punched hole wall surface is not smooth enough compare with drilled holes'.