I just looked at the motor on my water softner and it is turning too slow for this application. I am sure with a little research the right speed motor could be found.
I tried searching for schedule 80 5 ways and didn't find anything.
I did however find this company that has pre-assembled 5 way diverter valves with multiple options of flow direction and sizing driven manually, pneumatically, or electrically. I e-mailed them for more info, detail, and pricing. http://www.evsco.com/flow_patterns_4and5.htm
A picture is attached, 1st the electric, next the pneumatic, then the manual, and a stacked valve.
By the looks of it they are going to be just as much as OM's valves.
I found another website for a 5 way valve but it was a little over built, overkill, and not corrosion proof, it's pictured last.