[Arran]

You can also use 1Q5s as a substitute from WD11s, if they are rewired as a triode, I think there are similar subs you can use for 199s. I don't understand why people think they can only use newer triodes as substitutes for older triodes, why pay extra money for having two fewer grids? When it comes to 201As I can't see the point in using subs unless you happen to have a lot of a given newer tube on hand, if you can't find the globe versions you can always use the ST style ones. I can't see any advantage in substituting a 201A for a 199, 199s are much less common then '01As, probably because RCA brand sets (G.E and Westinghouse) were the primary users of 199s, there may have been others but not many.
Regards
Arran