You need to be waaaayyyyyyyy more specific about what you want, if you want any chance at all that someone would help you get what you're after. What class sub? What era? Etc., etc.
There are tons of 1/48 scale kits out there, for bunches of different class boats. Oh, and the "tower" in old boats was internal and couldn't be seen from outside. They are sails (US), fairwaters (US), or fins (UK). Maybe European boats have towers, I don't know. Anyhow, tell us what you want!!
"If you ignore the problem long enough, it will go away. Even flooding stops eventually!"