A 2nd hand Big Nikko would most likely be a good place to start, easy enough to range find well with (even I can do it
). I would look for a Mk1/2 to start with. Will be cheaper than a Mk3, but will do the job at least as well, some say better than the newer version.
If at all possible, try and have a look through/ have a go with a prospective purchase as 2 scopes of the same type can vary greatly.