Hi Sozi81,
i recently enjoyed building a seaport tug.I don't think that there is no difference in the two types.The supply ed radio gear in very poor quality and the 40mg gear is ideal,i changed my servo to a futaba 3003 and receiver.
To get a long duration run i would replace the battery pack with a 6volt 4amp sla battery.this will sit in the flooding box once you seal offthe inlets.
Motor choice i would suggest any thing from a 480 size to a 600.Mine is a Robbe 550 with a 2:1 belt drive, A good esc are the blue 50amp forward /20 amp astern advertised in Hong Kong
I didn't like the mast arrangement ,thinking it made the boat too tender in strong winds,the mast on my boat came from Graupner.
As for modeling it as a Italian tug try google or the page here dedicated to full size tugs.
I enjoyed building the seaport so much that i have picked up another which was going to rework as a 1960-1970,s tug,starting with a total stripdown and remove the raised centre deck to make a flush deck.Has any one got a tug in mind that that might fit the bill.
best of luck with your seaport Sozi81.