Unless you can genuinely and legitimately justify unique content for each I would either canonical them from the start or better still get them on one page.

I know it sounds like an easy long-tail win, but it can go horribly wrong.  I'm currently working on a site that is being heavily penalised as a result of a similar approach and we're having a nightmare getting the thin content out of the index.

My experience is that the .uk extension is a strong indicator for a local site and it creates extra work. US hosting, contact details and predominantly US links would help, however personally I would still be thinking about a separate non .uk name.

Ick - horrible markup.

If you are choosing the HTML element based on spacing then you probably need to look at your CSS. I've never seen an H tag used in this way before, it is certainly an original approach.  I don't think it'll kill you, but I'd avoid it if you can.

I would say that a bullet list is a more correct element for those breadcrumbs. I suspect that the thought process is along the lines of making them H1 will lend greater weight to them. It won't really work in that manner so you will probably be better served with code that is more "correct".