Wow, well, here in the U.S. that shelter's policy would be considered ridiculous.   Bunnies over 6 YEARS are considered risky, but not over six months.    Some vets here wait, especially for females, UNTIL six months.   I bet there are some rabbit rescue groups in Scotland that may be more rabbit savvy. 

A bunny over 2 years may be more expensive because a rabbit savvy vet should do a full check up and do bloodwork to make sure there isn't any other health issue that could cause problems, but it is very common here in shelters etc to have rabbits altered before six years old.   Check out this article from HRS. http://www.rabbit.org/faq/sections/...bsp;  and in that same article, be sure to scroll down to find out how to screen a vet to make sure s/he is rabbit savvy enough to do the surgery.

I bet there are some rabbit savvy people in Scotland that could direct you to a good vet. 

Here is a link to some rabbit rescues etc. in Scotland http://www.rabbitrehome.org.uk/cent...bsp; 

Keep us updated on what you find. 

I used to work at an animal shelter, and I feel sorry for all the animals....and the dogs, because their emotions are easier to read right away,  are even harder for me to witness being passed up. But at least there are shelters for animals so that they have a warm place to stay where they can get food and interaction at least from staff and/or volunteers.  I always felt the most heartbroken for a long time family dog, or any other animal, that the family decided to give up.  I always think how hard it must be to go from a home and family to a cage in a shelter.   It was so difficult for me see that.