Some of the auto parts chains sell red & white conspicuity tape in strips. None of the good / bright stuff is cheap.

http://www.google.com/search?hl=en&q=3m+conspicuity++tape&btnG=Search

The DOT C2 or SOLAS spec will give you the brightest tape. The 3M brand seems to be the brightest.

If you're only looking for a piece or three, I can send you that for free.