I meant a modulated neutron initiator, not the explosive detonator. India was still using vapour deposition of polonium to make theirs, around the same time. I'm no engineer but that sounds like it costs a lot more than $2000.
HN never ceases to surprise! I am really curious how you happen to know such details about India's nuclear bomb.
The internet probably. [1]
[1] https://nuclearweaponarchive.org/India/IndiaSmiling.html
The actual initiation is the easy part and would have been easy in the 70s, exploding wires that are subjected to a number of kilo Ameperes by some kind of avalanche, solid state switch.