First of all, i wish you a quick and speedy recovery.
Choices for the Bobber are limited and yout have not mentioned budget.
So, i would say if budget is not
a factor THE best choice for you would be a DAY LONG
seat from the USA. These guys will make a seat designed specifically for you and any issues you have.
I have had a number of their seats; both service and quality are fantastic. There may be a waiting list, though and you will have to pay shipping + import duties which will be expensive.
They will use your existing seat, so you will be seat-less while they work on it.
Also, the seat probably won´t look ¨good¨. Will be (in my opinion) a case of function over aesthetics.
Secondly, try to find a company within the UK that can reshape and refoam the seat for you.
I have no first hand experience with any such firms in the UK, so can´t recommend anyone personally.
Anthony Mclaughlin from the UK Facebook Bobber Group did a nice recover job. Maybe you could contact him?
I have spoken to him and he is very friendly. Though i do not know if he has experience with actually RESHAPING a seat. If not, maybe he can recommend someone.
Here is a screenshot of his work:
Third option is a Corbin. But there are very limited reviews regarding their seat and refunds are a complete no-no (i spoke to Corbin UK and they confirmed this).
I have a coccyx issue/pain and asked what happens if the seat does not resolve my issue. They just copy-pasted some spiel about comfort and said that they cannot offer a refund under any circumstances. Simply NOT good enough if i am going to spend 520GBP.
I am still weighing up all 3 options above.