Clock with 2 different times

It may be possible to use command blocks (which can be given via /give [player name] 137 1), or you may have to create a mod of your own with that feature. Sorry that this isn't a specific answer. I will do some research and get back with you.

The first solution that comes to mind is a setup like this.

Two different timers that both converge into one line of redstone leading to where ever you want it to go.

A hopper clock has an analog output (just grab the signal from the comparators you use anyway). You can combine this with a device that turns on only for a specific signal strength, like the one generikb uses in this video.

That way, you get an increasing signal, pulsing once when a specific strength is reached. When the signal retracts, it pulses again. The timing between these pulses can be configured seperately by changing the amount and type of items in the hopper, as well as the distance between the comparator and the detector (mostly trial and error). I suggest using eggs or snowballs (or any other block that stacks only to 16), so that the change in signal strength per item is larger.