I kinda agree with both of you.
1. As a new to cats, you may be better off starting with just main sail. There is much to learn about handling your H17. If you intend to single hand your H17, you will find it handful even in a medium air with just main. Just make sure you use the SE bridles/forestay or install a spreader. Bridles would be longer on H17 SE and shorter on H17 Sport. Unless you go in less than 5 knts, you would be risking a serious damage to your hulls. Better option is to get a spreader, as James suggested.
2. Moving forward, a super jib would be a great addition for a light/medium air and for downwind. The H17 is otherwise underpowered and not as much fun. Another useful upgrade is a bigger squarehead main. Mine is about 10 sqr feet bigger comparing to the original pin-head main.
As to your original question, check the H18 parts guide.
http://static.hobiecat.co…tal_assets/H18_Parts.pdf
This will give you a part number which you can order from any Hobie dealer, http://www.murrays.com, etc. Your pictures are still not accessible, but it sounds like your setup could be similar to H18.
To clarify, Hobie 17 was designed as unirig (main sail only) boat, but later offered both as a class legal H17 SE, and equipped with jib, Hobie 17 Sport. H17 Sport would have "Hobie Sport" decal, as on the video, is not a class legal boat.
The Sport version would be originally more expensive, but in today used boats market, there is very little difference in price.
Good luck, and welcome to the H17 club.
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Jack B
Hobie 17
BC, Canada
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