What you're looking for is pinstriping tape. It comes in 40-ft rolls at my local AutoZone store in various colors and ranges from $3 to $17 per roll depending on the thickness, how many stripes, etc. Online dealers have a very much better selection of colors.

Have fun,

Laszlo

I usede auto pinstripe tape to cover the paint/varnish transition on my Ch17LT.  Works well, easy to apply and holds up well.  When it is time to revarnish, I remove it and apply new.

   West Marine and most auto parts shops carry it. Comes in a roll and has a backing to pull off.  I used this on my Jimmy Skiff II. 

https://www.westmarine.com/search?Ntt=pin+stripe

Google Pin Stripe tape and you get lots of options. 

https://www.customautotrim.com/pinstriping-tape/specialty-pinstripes/ps-ww/

   Very helpful responses, thank you all!

Michael