I'm willing to pay for hidden sets.

I'll get straight to the point I want the set Suat Mamat, Aurel Guga, Alaattin Baydar and Adolf Scherer, Anton Malatinský, Nikola Kovachev, Panayot Panayotov and Krum Yanev.

Let the author of the aforementioned groups speak out.

That's not how it works. Someone else suggested something similar not long time ago. This website isn't a players set marketplace.
People who can and want to donate money, they do it out of respect for the keeping of the forum. No one pays with the goal of seeing some sets.