What you can't do is take a calc that has the character at Mach 1,000 speeds and apply it to another calc.
What you can do is take the minimum stated / shown speeds and apply it.
For instance, if Thor's lightning is calced at FTL+ speeds in one comic, you can't apply that to every comic involving Thor shooting lightning and characters dodging it. But you can apply the speed of real lightning to it.
What speeds are there in the exact scan that we can quantify based on real stuff? Bullets, falling objects, cloud-to-ground lightning? That way, you can base the calc on something that is not on another scene or time entirely.
Ugh. Can you just post the scans in question so people can have a look at it?
I find a simple solution,As the character gives a saber shot before being countered by the character I will use the record speed of a saber used by a man, the man comes to cut objects at 10m from him going at a speed of 500km / h