The "SCA" 80-pin to "wide" 68-pin SCSI adapters almost always have a 4-pin power plug on them.
Here is a cheap one you will find all over the place on the internet:
I can garuntee you it is not U320 compliant though, its only a 2 layer PCB and you will likely have issues running a U320 with some drives or adapters. Another dead giveaway besides the cheap PCB is the text "Ultra4" on it. There never was Ultra4. SCSI changed to the names Ultra160 and Ultra320.
BUT even if you get good SCA to wide SCSI adapters, it will be very difficult to get all 5 drives running at U320 or even U160. Even the good adapters add a lot of capacitance to the bus which degrades signal integrity.
You best bet is to get an SCA hot swap bay or external enclosure if you want to run that many SCA drives. Here is one example:
but I think you can find some for cheaper.