Where to purchase a quality chronograph

[Smokinyotes]

This morning I had done up a few test loads for my 270. Started out with 53 gr of H4350. Velocities were 3501, 3496, 3501. Well I know this isn't correct so I repositioned the chrony. Next loads were 54gr H4350. First shot 3040 next two shots err1. I'm really sick of using this chrony and thinking I should look at something that is actually dependable. Any place to purchase a quality chronograph in Ab or do I need to get one from Sinclaires.