TOW's: Antiship Capable?

[StainlessSteelCynic]

If the Stinger missile locked on to the heat source it could theoretically be used but anti-aircraft missiles typically have very small explosive charges.
They don't wreck enemy aircraft so much by explosive force as they do by hitting the plane with lots of fragments. Aircraft are normally made from thin aluminium and have a lot of fragile mechanical & electronic parts that a even a few fragments can ruin.

Ships on the other hand are typically made from steel or thick aluminium and have much of their fragile equipment located behind thick walls or in inner rooms. With a Stinger you might destroy the funnel of the ship but that's not going to do much of anything except maybe injure some of the crew.

[Targan]

Kalos, perhaps you were thinking of the M47 Dragon ATGM? That's man-portable, shoulder-launched (well sort of, it has a bipod) and wire-guided. IIRC Paul Mulcahy was a Dragon gunner. http://en.wikipedia.org/wiki/M47_Dragon

[raketenjagdpanzer]

Of course there's also the FGM-172 SRAW, which fits between the AT-4 (M136) and FGM148 Javelin ("Tankbreaker").

Unfortunately the SRAW has been taken out of the anti-armor role and is now just an "assault missile" equipped with a blast/fragmentation warhead. However for the OP's purposes, that might work better.