Would the waterways recovery group be a good port of call? Whilst many locks restored are sort of there very much often needs rebuilding and the original methods of construction are in evidence.
As mentioned this would include the course that the sluices take. It seems important to get that right. Top paddle sluices that when opened at any speed pull boats in a hurry towards the top gates and cill isn’t a good idea. That seems likely to cause more structural damage over time than ones that fill swiftly while maintaining the boat position in the lock quite nicely. BCN, Coventry or S&W are examples of good fillers, Oxford and Cheshire locks less satisfactory.
It’s noticeable too that the Coventry canal locks, Atherstone and Tamworth locks seem to fill at a slower rate than BCN locks.