A long time ago they made rate multipliers (74167 is a decade one) . You could set the rate you wanted on the BCD pins and for every 10 clocks into it you could get out from 0-9 pulses. So all you would have to do is set it for 8 pulses and then for every 10 (52) you would get 8(42). The pulses would not be evenly distributed (jitter) but in your case it wouldn't matter.
In old nc machines this was a method for doing linear and circular interpolation without the need of a cpu.
I still have some in my junk drawer.
sn74167.pdf (296 KB)