Civil reactors are really not particularly good machines for manufacturing weapons grade Pu. Even countries with advanced civil programs will still typically use special weapons reactors for cooking up military material.
To get weapons grade Pu from a civil reactor would require one with full on load refuelling capability (CANDU possibly. PWR, No!) and you would be unlikely to be able to get away with using such a reactor for a clandestine project.
Clandestine bomb programs are in any case more likely to go down the HEU route. Easier to hide and easier to make Bombs that work first time.
(Ironically, one possible route for a non-nuclear country to obtain Uranium for a clandestine weapons program is from Coal fly ash. Coal contains significant amounts of natural uranium. The irony is that the energy value of the Uranium in the coal is comparable to the energy value of the coal itself and that the radiation emissions from a Coal station are many times what would be tolerated from a nuclear power plant...)