Hi Doug, milling strips yourself will always be cheaper. The cost of Western Redcedar boards will depend on your geographic location and the disposition of your lumber yard. One board foot (bf) is a one foot length of 1x12. So you would be paying $3.80 per bf which is not out of line. I live in the Northwest where the trees are everywhere and felt lucky to pay $2.60 per bf. Check around several places. I have one yard that charges a bit more but has better dark boards. Below is a method for calculating the number of strips required for your boat; I'm not a math genius so the logic could be totally wrong. I ended up getting a little confused at the lumber yard anyway and didn't purchase quite enough but I can always go back for more.

Good luck with the project.
- Chip

Here's how I estimated the required footage: Find the coverage area of the strip you are using. That would be about 5/8" for 3/4" strips because you will lose 1/8" on each cove; that is .625". Find the perimeter of biggest mold in inches and divide that by .625. That should be the minimum number of full length strips required.