Wow, I also have a 2012 P3 and would love to find the risers, too.

I am told these are compatible, but I'm hesitant to pull the trigger and purchase without verification from someone more experienced than I. None of this would be a problem if I were as flexible as I used to be!

https://www.speedmetrics.com.br/...ts/straight-spacers/

They were as rare as Hen's teeth 2 years ago, and I'm sure the situation hasn't improved. Fibre-lyte make compatible spacers from carbon fibre though- which I think you should be able to stack up, perhaps with a cross brace at the top for stability. https://www.fibre-lyte.co.uk/...ycles_timetrial.html. Their standard is 6mm, but I imagine they will do a 10mm if you ask.

Thank you, Tim. I sent them an email this morning making an inquiry as to whether they are custom-making 60 mm risers and whether they recommend a cross-brace. Sure appreciate your referral. Thanks.

No problem. I doubt if they'll do 60mm, as they'll cut the risers from a CF sheet, but they should able to supply multiple 10mm ones.