Shared page content between sites

Ok, I know I’m not the first to try and figure something like this out. But, I haven’t been able to find any definitive answer on whether this is possible, or, if so, how.

Here’s what I want to accomplish…

I have a record label as my main site, which we’ll call ‘record-label.com’, set up as my main WPMU site. I have subdirectory sites set up for two bands on the label, ‘band-1.com’ and ‘band-2.com’. Though each site has its own style and a majority of its own content, some of the content overlaps. Examples of overlapping content being a Contact page, an Events page and most importantly an online Store.

Is there a way to have one of the band sites display the main content from a page created on the record-label.com site with its own framework? As in, wrapped in its own theme? An example being the contact information. Can the data contained within the ‘contact’ page on record-label.com be displayed on the ‘contact’ page on band-1.com without leaving the site or looking any different…with the band-1.com theme?

Also, is it possible to have a WPMU-wide store? So, if someone on the band-1.com site adds a T-shirt to the cart, they can then go to band-2.com and add a CD, then checkout once?

Any suggestions or solutions will be much appreciated. I know there is a way that this is possible. I’m just hoping it’s possible in WPMU, and not too terribly involved.

Thanks in advance!