I have a 34 feet houseboat with a Chrysler 318 driving a Paragon v-drive -
the problem is that no parts are available anymore for this tranny and i
would like to change it to somewhat more modern. I have two choices:

Stick with the propeller and shaft model and buy a Twin Disk or ZF v-drive
transmission

Get an I/O and install it on the boat.

Now i get very decent performance with my engine and propeller combination
right now. Low speed (8 kts) operation cost is about 12 $ an hour at 1500
rpm and high speed (18 kts) is about 40 $ an hour at 2700 rpm. Top speed
is 22 kts. I have no experience whatsoever in I/O and i would really
appreciate to receive comments on this.

Cheers

André