As above a Big Nikko, but if its second hand suggest you try before you buy as there are good and bad ones about £700 new. Falcon T50 about £450 new not that far behind the Nikko, then Nikko Nighteater £200 ish and for around £100 a ZOS 10-40x60 off EBay you do get what you pay for with scopes.
Look out for a second hand Big Nikko MK1 2 and 3 are very good , the Zos and Night eater in my opinion are no good for range finding. Plenty of people buy them because they are cheap compared to the real deal , then they try and sell them.
About as much use at field target , as a life guard at the Olympic swimming pool.