Money does have a way to influence lead times. But have you checked the lead tomes for liquid filled transformers lately? If a factory?s production line were booked up for months and there is a need for a replacement core and coil people don't realize that an order that is put within an existing production schedule has to displace other orders. This causes the existing orders to miss their scheduled ship dates.
Extra money for overtime and the premium production space left to accommodate emergencies come at a premium price.
The are also transformer repair services available also the may be able to repair the transformer in a shorted time.
Then the question is if it was your transformer that you purchased brand new where would you like to have it evaluated, tested, rebuilt, and final production test performed? The manufacturer may have their engineering service group do the work but the fact remains if their os internal damage which I would think that there would be the factory would have to manufacture a new core and coil anyway.
As an application/sales engineer for a dry type power transformer manufacturing company it?s quite a challenge when you production schedule is filled up for 14 weeks and are already working overtime to maintain scheduled ship dates. There is just no way to squeeze anything in even with premium dollars without making other customers angry. Liquid filled transformer manufacturers compete with us in a way and we are well aware of their very long lead times. Where either type are acceptable in an application dries have a much-shorted lead-time but their inherent cost is considerably more.