https://henryrobb.wordpress.com/2011/05/04/wwiitugs/

Doug posted this link 5 years ago and a couple more too when Marky was looking for plans.

Plans are for HMS SAMSONIA

Found the plans at Tony Green Steam models in the UK.

Good morning, I have been looking at those plans but they are for a Harbour tug. I’m looking for the plans for the Bustler class salvage rescue tug. She was 205 feet. There is a fellow on here “Marky” that was building one a few years ago but I’m not sure if he is still building it.

This one comes with build notes. You could eazily scale it up as a lines plan is included..
https://www.vintagemodelplans.com/products/full-size-printed-plan-a-near-scale-harbour-tug-bustler-18-l-o-a-power-electric

It's in the UK.