I have avoided the search for Vintage Valves of this type for some time.
There are prices being seen almost appreciated 100% since I was last searching.
My purchasing method, where an agreement with the Vendor is in place that a Tube will be returned for a refund, If my friend with their Valve Tester proves the Tubes supplied measurements are not quite close, when measured on the friends calibrated tester. This method has assisted myself with getting top draw Valves.
With the present prices such a agreement will be even more important, if I have to enter back into being a buyer.
Caveat Emptor - Caveat Emptor, most valves supplied will produce a sound, but what type of Valve is being supplied.
As made known in a previous thread on the E88CC, a New Matched Pair of Gold Lions, had one Valve measuring quite unusual when tested and it was strongly advised not to use it as the Circuit could be detrimentally damaged.