Club Champion is a fitter and should be able to provide that information. You can find a local Titleist account who has a fitter and take your numbers to them and see if they can come up with a combination that comes close to what CC has fitted you for. Have found that a number of folks in this area are doing this.

I checked Titleist catalog and it does carry any shafts that will match exactly every number of the Diamana RF50 R Flex. The weight on that shaft is 55.5 gms, 4.4 torque, with a mid launch. You can find them on line, but not thru Titleist. . .

Why not just order through Club Champion? If you "loved" the numbers and performance, then that's the combo for you. Another shaft is just a shot in the dark.

The marketing advantage of CC is they have shaft options you can’t get from the OEMs. I have no idea if they work with OEM shafts. In this case, they didn’t. Getting a fitting but not taking the recommendation seems a little awkward. Then again, so is the cost of the custom build at these type of locations.
The Diamana RF50 is the 4th generation of the Red Board. That was a high launch shaft. The Titleist options would most likely Kuro Kate Black or the lightweight Fubuki shafts. Depending on your swing, a mid-high launch shaft like the Tensai AV Blue would be another option. But you should find a Titleist fitter to see which gives you the best numbers. Most fitters will reduce/wave the fitting fee with a purchase. Titleist does not undercut pro shops, so the shop price will be the same or less than buying direct.

In the Titleist custom club options which would match close with your Diamana specs of 56 grams and 4.4 torque would be:

GD Tour-AD BB-5 R1 56g. 4.3 torque high launch.

GD Tour-AD IZ 5 R1 54g 4.5 torque M/H launch.

GD Tour-AD XC-5 54g 4.2 torque M/H launch

EF Riptide CB 50 5.5R 54g 4.9 torque Mid launch.

I would try these at a Titleist fitting that closely matches your Diamana specs. They should have those available to try I would hope. Good luck!!

Bax,
Those are upgrade shafts and he is asking for stock options. Just a heads up.

Comparable shaft options would Kuro Kage, 50g, Reg flex, could also try Tensei Blue Raw, Reg flex. Only way to find out is to go get fit by Titleist fitter to make sure your dialed in. Good luck!