Sometimes you can’t find any standard office furniture product which will fit in the space you have, or will do what you want it to do, and its such a small job that most office furniture dealers won’t be interested in quoting to make it for you. Rather than give up or compromise have you thought about making what you want yourself.

It does help if you are a practical person, but even if not, you probably know someone who is and could be coaxed into helping.
Desk frames and tubular legs can be bought from furniture dealers, or from specific office furniture component manufacturers such as Hafele or Heltich. If you can stand the queues Ikea have a reasonable range of table legs and tops, and some of the larger DIY superstores often have a good range.

The above mentioned component manufacturers are also a good bet for cable ports, cable tidies and trays, drawer internals and locks etc, so you really are only limited by your own skills. Desk tops can be purchased and cut or scribed in to fit. Straight lines can easily be dealt with by using a specific MFC saw which only costs a few pounds. These saws are available online and will cut furniture board easily and with almost no chipping of the surface. If you have to deal with a curve and have or can borrow a jigsaw, you can buy a woodsaw blade which has teeth designed to cut on the downstroke, which minimises chipping.
Most table legs can just be screwed on with course threaded wood screws but if you feel like doing the job professionally then 6 or 8 mm thread inserts can be purchased from most good hardware stores and office furniture component manufacturers. These little castings have a coarse thread on the outside which screws into a 10 mm hole drilled in the desk or work top, to leave a recessed screw thread designed to take standard bolts or set screws. These fittings really distribute the load from the fixing into the worktop much more efficiently than a standard woodscrew.
If you are building your own desk, using a standard steel desk frame it is advisable to use these inserts as the fitting method.

Long bench like desks can be made by using a standard wood finish kitchen work tops and sitting them on either steel desk height pedestals or tubular legs.

The top can be scribed in or just butted up to your existing walls, and the gap trimmed with a little wood moulding.

Monitors can be mounted on the wall or even suspended from fixed monitor stands which are able from many online sources. Cheap hole cutters can be bought from online hardware retailers and data and cable outlets can be mounted on the desk.

The result is a tidy and functional work area which can used by the family and integrates with the room

Even standard two door cupboards can be modified with cable access holes and ventilation grills to take your CPU and other electrical equipment. Ventilation grilles and access ports can easily be added to allow you to put whatever you wish inside the cabinet.

So if you are really stuck consider trying to organise something yourself rather than having to compromise. You will save money, and get exactly what you want and you might even enjoy the experience