Can't help you with the length, but I'll offer one bit of advice. Take a look at the Ronstan Sealoc calibrated turnbuckles. Less total throw length, but an order of magnitude easier to adjust. We went to them for our shrouds, when we replaced them. (New hardware, every quarter century, that's my motto!) We'll do the same on the headstay when it gets replaced in a season or three.
- David
