I had a great conversation with John at Tube Store today and bought two KT150's at $139 each after my back-up stash of eight KT 150's purchased three years ago from another source turned out to contain one cracked tube (lesson learned-open the box and check your tubes even if you have no intent to use them soon-no matter how good the outer box looks). Since my ARC Ref 150 SE requires matched pairs, buying just one new KT150 was not an option. John mentioned Tube Store is getting low on KT 150's at the moment. And-the source I bought from three years ago has no Russian tubes at all which I find amazing given their otherwise huge inventory. It seems to me that distribution is uneven and depends upon connections though that is just my assumption.
And yes OP, I had the same impression as the other guy-that you were accusing Tube Store of price gouging.