Hydraulic Trim/Tab Pump

[chumbucket]

It may not be the pump. Maybe just the pump motor is toast.
The motor and pump assembly should be either a Prestolite or an Oildyne. My guess is that it's an Oildyne pump. There are a few companies that sell new and reman pumps and motors or whatever other parts you may need. Either way, give these guys a try;

http://www.go2marine.com/frameset.js...ction=DoSearch

http://www.apimarine.com/
:)