Hi Phil,
Great work on putting together so many GB's. You have the same tastes as I do with parts so your choices are always interesting.
I've been a little concerned with the current GB based on past excuses of the supplier and the feedback today does not help, a minimum of 6 extra weeks probably more. As I understand it you have received goods from this company before but they have a reputation for late delivery, is this correct? I appreciate you have said you will look to run these differently in the future to avoid or limit these kinds of delays.
Based of their email to you the suppliers are seemingly happy to pay(reimburse) for the fittings we find our selves, but that would probably have to happen through you, as I can find a supplier easily for $600 made on the spot for me, so there must be some level they are willing to pay to, maybe $80-100 based on the GBP price of the connections? I know it is a pain but would you be willing to try and find a local supplier of the black connections with quick turn around? Then organise a refund through yourself (before purchase).
Personally I'd prefer to receive the majority of the goods I paid for so long ago, and await delivery of the final black parts. That way I have 90% of what I paid for and am happier waiting for the final parts. (Unless they need to be specially fitted).