I couldn't find any for sale in the US. The only websites I found that actually sell it were in the UK. I didn't check it out, but it's possible they would ship to the US. Just do a search on Google for valerian +cat and you'll find something.

Guess T & P will have to go without for the time being. Although....I might just try planting the plant myself next year. But then I might have every cat in the neighborhood fighting over it.