There are a few to choose from but none of them cheap. You need them to fit a 50mm stanchion and buy ones with a 1.5" to 2" rise on the stem or you will find them much too low.
In fact I ended up fitting a set of clip-ons from Spareshack also above the top yoke. They had optional bolt on risers but I didn't use them because the reservoirs fouled the fairing. They were much cheaper than the fancy ones though. I subsequently sold them to Eonan. If he still has them he may be willing to sell them on to Aircooled.Derek after your advice when I raised this topic I have (sort of!) decided to drop the forks and fit a straight clip on if possible. Cost is a fraction of ones with a riser on them and I don't think it will affect the handling to any extent that I would notice.