I'd have to consider my overall goals and long term intentions with the car. Are you looking to have a "show car" or just "transportation"? How much total investment have you planned for the car overall and how does the paint cost fit into that? What else does the car need in terms of repairs, improvements, etc - and the associated costs? Is this more than a "car" to you (some people seem to be 'heavily involved' with their X1/9, while to me it is just a heap of parts)? And other such questions. In other words don't lose sight of the big picture.
In particular those estimates sound quite high in my experience, short of a show car result. Shop around; the body/paint industry is a HUGE money maker and the shops are making WAY more profit than you could ever imagine. One of my richest friends started with one body shop, profited enough to open three more, which profited enough to buy a Honda car dealership, which profited enough that he owns a mega yacht, multi multi-million dollar homes, property in other countries, a plane, and on and on. So don't be taken in by their overly priced estimates. It isn't magic what they do - the actual work is typically done by laborers that never had any formal training. I've seen lots of examples where a shop convinced the owner the only way to do it right was to completely strip the car to a bare metal shell and start over at a exorbitant cost - only to end up with a horrible result. Trust me on this - you can get top-level excellent work done for a fraction of those numbers.
That being said, you may decide not to have the car completely redone. Most of the pictures you showed really aren't that bad. They could be ground down, treated, filled, and the paint blended in with many many years of satisfaction. It all depends on your answers to the initial questions - for you, your car, and your personal situation/goals - not mine or anyone else's.
