User blog comment:Xmark12/Calculations/Feats For My Characters/@comment-26221691-20161111193731/@comment-28644276-20161111195558

I dunno about the low ball, but I did the High Ball with 93 Billion light years and got...

93 Billion LY =  879 847 933 950 014 400 000 000 km

Dividing that by 5 minutes (60 x 5 = 300 secs)...

2 932 826 446 500 048 000 000 km/s. That's  9 776 088 155 000 160c if I didn't mess anything up. But since Xmark was using the more exact value of 299 792 for lightspeed, I'll use that as well for a "slightly" - absolute highest, I believe, result.

High End: 9 782 870 945 522 388.85c