I'm new to the forum so I will respect the system and not post names and numbers at this point, but if you want the acoustic bass sorting out then feel free to PM and I'll put you in touch with one or both of these chaps.
A few years back there was a guy called Shane who did all of Sound Control's repairs who was excellent but I don't have his number and can't remember his surname to look him up!
Jim Fleeting is in Ripon, not so far, he did an excellent bone nut job for me a while ago and will tackle owt including new builds and best of all he's really a bass man who also does guitars rather than vice-versa.
Here's a link www.guitarrepairman.co.uk
Apologies if Jim's already been mentioned and I missed it.