It depends on their damage control capability (and in this regard I do not believe there is anyone as good as the US...they simply have the best training and experience). it also depends on what facilities are available and how far away they are...also, in war time, it depends on what conditions those facilities are operating under. If they themselves are being threatened or attacked, then it makes a difference.
In World War II there were several times, with US Aircraft Carriers and other vessels that what was thought to require several weeks repair were litterally turned around in a single marathon overnight effort so the vessel could go back into harms way.
With today's electronics, depending on how well they were built for maintainability (ie. can you take a damaged unit out and simply plug in a new one, or is there all sorts of dissassembly and rewiring required) those parts could be turned around very quickly depending on blast damage or the lack thereof.