Power meter for older FSA gossamer cranks
I have a planet x carbon bike about 8 years old. Its got an FSA gossamer crankset. The BB reads 'megaexo bb8000/6000 and BC1.37x24. The crank arms are 172.5 with a pinch bolt. So, anyway I was hoping to get the Stages power meter but it seems the newer FSA crank arms don't have the pinch bolt so are not compatible. Can anyone recommend a power meter that won't break the bank (completely) which I can use on this set-up, or do I need to upgrade my crankset completely to benefit from a power meter? I've got a direct drive trainer so I can't use the rear hub option.