Dishwasher Pump Hose – Again

I loaded the dishwasher and turned it on.
I noticed some water on the ground and figured I had spilled it while loading the dishwasher.
I cleaned it up. When I came back there was more water on the ground!
I opened the kickboard and found more water under the dishwasher. I turned it off and pulled it out.
Took pictures/video show it was leaking from the pump, again.

Seems like the pump just disconnected. Not sure if it was fully disconnected while running or if moving it caused it to disconnect completely (and it was only slightly disconnected previously).

In any case, I attempted to reconnect it. Very difficult to do since the pump is bigger diameter tube than the drain on the dishwasher.
Whomever (my father in law? or my step-father? or someone I paid?) fixed it last time (in 2012: http://gabe.misura.org/2012/09/08/broken-dishwasher/) used this clear rubber tubing:

And stretched one end to make it “fit”.
I took it off and cut about an inch off because it was too long. I put it back on.

The original part, seem here:

I put it back together, but the seal is not good enough, it is still leaking (very slowly).

Where in the heck am I going to find a rubber tube that is different sizes at each end?

I’m sure by now you’re thinking, just buy the part from the manufacturer. Sure, for $253.97 for a bunch of parts I don’t need:
Dishwasher pump and Motor Assembly

Sear’s Image of Pump and Motor Assembly

Sear’s image with part circled:

Someone else sells the part, combined with other things I don’t need for $104.30: Kenmore Dishwasher Pump Hose at Repair Clinic. Same for Home Depot.

Where can I find what I need?
Or can I “melt” the tube I have to better fit?

Space between the pump and the dishwasher is like 3/8″