I have found the WESMAR thruster product line to be very good for my usage on one of my boats.
You might want to take a closer look at their line.
They have electric & hydraulic.
I have used them for a long time & are very durable.
I have a 13 HP - 24 volt electric as my stern thruster & it works great.
Reasonably compact & attached on back if transom - NO through hull tunnel needed. See picture below - it is the little sideways 10 inch Dia. pipe that is about 3 feet long under swim step as an example to show what it looks like installed.