A hot section price depends on how much is trashed in there. But it will probably be in the $30-50K region, so it's on par with a piston engine overhaul. However, PT6's are kind of expensive to overhaul as they have such a stranglehold on the market that they can charge through the nose. Friend just did his TBM and it was well over $300K, but that's a bigger engine. Count on it being a good $250K at least.
A Seneca here in the states can probably be flown for $300-400/hr. But in Europe with the painfulness of Avgas it makes it a more expensive deal, probably. And inconvenient. Turboprops normally don't cost more per NM to run, but do cost a little more per hour. But when you factor in the much lower JetA1 price in Europe, there it actually makes more sense than here in the US.
Sometimes an older Garrett powered legacy twin can end up being cheaper to run than a TP single. Garrett's have 5400hr TBO, cost less to overhaul, burn about 20-30% less fuel than the PT6's. Add that up and a TP twin might be on par with the bigger single turboprops. Probably not the case with a Meridian in operating costs, but certainly cheaper if you factor in purchase price. MU-2's and Turbo Commanders 690B are the most common Garrett-powered twins.
Good luck!