Update:

Recently managed to make some more progress on building this amp after I ordered some stuff online from Evatco, I've got all the valve sockets wired up to the tagboards and pots, all I need to do to complete building all the circuitry is to order five new vactrols online from Evatco, then all that's left to do is order the new power and output transformer, choke, and a full set of JJ valves, plus some more 600V DC rated vintage-style cloth covered wire, and then I'll be able to finally complete the build process before doing all the testing/debugging/biasing, and then some play testing, will post some links to some demo recordings of the amplifier once I know it is all working correctly and sounding good.