Hi Jon,
Just to say I am enjoying this thread of yours and it's good to see you do not just "give up" if some part is not supplied, I have built a few 7mm coaches and I must say "most" of them do not have any sort of brake detail added.
To be honest the brake detail is needed especially in 7mm as it stands out that much more, I have built a GWR B set and a SR/BR bogie luggage van recently and I had to raid my scrap box to make a reasonable redition of what should be there.
Just a quick question those rivets you are using look the business, are they from Scale hardware in the USA ?
ATB,
Martyn.