Just in case somebody finds themselves in a similar position - I'm not sure why the new union didn't work - I tried 2 washers without success and the brake pipe worked find with the original union - I've found what I think are the original unions on
eBay - may be worth considering stocking up on one....
Of course, my brake pipes now have to be replaced - but I'm getting pretty adept at that now - so, progress and experience, by some definition
