4 or 3.5mm scale bricks, tiles and pipes

I'm trying to locate a source of 4 or 3.5mm scale brick stacks for use around a brickworks model. I have found that Harburn Hobbies in the UK do something suitable for the bricks, but I wondered if anybody knew of any other sources, especially on the HO side. I'm also after tile stacks and pipes for a similar use. I thought there might be something in HO scale in America, but being in the UK makes this more difficult to find. I've done some searches on the web, but not found anything yet.

Any suggestions?

Thanks

Stu