According to this page: http://blogs.msdn.com/b/slange/archive/2010/01/26/it-s-official-vs-2010-branding-pricing.aspx (found by googling 'tfs cal pricing') a single CAL is $499, which is the same price as the TFS Server ($499 new, $399 upgrade).
So at RRP, TFS costs:
- $499 = Server (w/ 1CAL)
- 9* $499 = CALs
For a total of $4990.
If a company can afford to pay 10 full-time employees, then $4990 isn't a major expense (of course, neither is $499 for a single developer).
As for CALs themselves, I think you need to contact a reseller for those. I get my SALs (similar, but different) from Insight UK. Insight do TFS SALs, but I don't know about CALs because I can't see them on their website or by searching for them. Give them a ding: http://uk.insight.com/en-gb/information/contact