By far and away the best place in the UK to have spacers made is Superforma. If you google PCD adapters, Superforma you will find them.
They will make any combination of PCD and hub bore & centre bore (within engineering constraints) you could wish for.
They generally come in around £140/pair and within two weeks. Not only that, they even e-mail you updates of where they're up to machining.
Here's some they did for me:



from memory they converted 5x100 and 56.1mm hub bore to 5x114.3 and 67.1cm wheel bore. These were 25mm deep and had their own studs incorporated.

regards
Iain