I'd suggest sticking with a gunboat. Cruisers and battleships are for chumps (no offense to the chumps out there). :P
Unfortunately, there aren't any Zoner or other civilian gunboats available. I believe someone was working on one for the next mod version, but I don't know if it was ever finished. But, since Zoners are neutral or slightly-friendly to most other factions, they may be able to get away with another faction's gunboat with a decent RP story behind it. I'd say the Rogue Gunboat or possibly Rhineland Gunboat (Rhineland needs the money, so they might sell a minor capship to any lawful with the cash).
