You can still get pens for any Wacoms. If you're in the States then Coolgraphics.com can provide all your pen based needs, Wacom europe has it's own store as well.
I am from Austria/EUROPE. Coolgraphics is an option but shipping and possibly customs might exceed the cost for the pen. So this would be the last option for me. I mailed Wacom Europe and got a negative anwer for the availibility of intuos 1 pens.
So I was hoping for defective/killed tablets as the old tablets on ebay are still quite expensive and also quite rare.
Regards
Marcus