If my memory serves me correctly, this project involved a client’s desire to keep her dog’s from disturbing guests, while still allowing the dogs to remain near their food and other needful amenities.
We’ve done a number of these type of door projects over the years. Installing doors between preexisting finished interior walls for a myriad of reasons from pet-control-barriers such as this project, to sound abatement as well as heating concerns.
Even if you have an unusually sized opening, the cost of custom sized wood doors, as it relates to the cost of stock sized doors, has greatly diminished over the years due to an increase in the competitiveness of the market and the various door manufactures’ desire to cater to that market.