I'm very happy it all worked out for you and Crack is working as it should. It is a great amp indeed! One of the best price/performance ratio's available. And for what it can teach you in the journey of building it and all that comes after, one of the best amps you will ever buy.
Personally, i think buying NOS or old tubes comes with a calculated risk for the buyer. Although most are generally reliable products they have had a long shelf time before you get them. And the noise issues with these old things can't always be checked for. And they can appear after some use without any symptoms prior to that point.
Second. I think a company can't be held responsible for the price you paid for a spare set of tubes. As you can buy tubes for a few cents a piece when you are lucky (or free even), or pay hundreds of euros for a single tube.
I know i'm not making any friends with you right now. This is a personal opinion. This is not at all the Bottlehead company opinion/policy. In general i think the support received from Bottlehead is among the best you can get. They stand behind their products and are always willing to help out a Bottlehead user in need.