I found the following bench strop available with an option to order with the either the smooth or rough side of the leather upwards:
Leather Bench Strop, 2 Sided, Hone Edge Razor Sharp - eBay (item 180404487029 end time Oct-05-09 11:23:12 PDT)
What do you recommend for Chromium Oxide, smooth or rough? I've emailed the seller this question but I'm concerned he might not be knowledgable concerning straight razors.