I buy nearly everything from the USA.
Learn how to use the Mouser search and project facilities. The larger orders take around 4 working days from Texas, duty paid too, with free shipping. Their customer service in the UK is excellent too.
JMI Music in Texas is a good source for Mercury iron. I like it and Redplate uses it too.
Doug Hoffman is really useful for components.
Teflon wire from Big Daddy on ebay UK.
If you want boards and chassis that fit, jborders and CE are the way to go IMO.
When alls said and done. in your shoes, I would get a Ceraitone kit and pop some nice iron it. You can then tweak and mod that to your hearts content'
I have just finished a scratch build AB763 Deluxe ground up build. I don't look at the cost when doing these as economy doesn't come into it. I just build it how I want. It is still a lot cheaper than 2 Rock though