Well, it looks hopefull for me.

But on the other hand I've seen many quite reliable Russian sources claiming that 53T6 and PRS-1 is the same weapon. For example, a book about history of "Almaz", former KB-1, a head developer of C-225, or (by the way!) a dissertation work of Pavel Podvig about ABM, written in 2004, when he stydied at Moscow. So, the question is still exist...

Yes, I am thinking about buying Podvig's book. The bad thing is: the Russian version of this book is exist but not avaliable in Russia! So I can only buy English version in US internet shops.