Jeremey - I'd consider just ringing up some of your local vineyards and asking who they use. You probably get some excellent local recommendations.
We have a vineyard being setup next our house here in the UK. The owners also have vineyards in france. For them it worked out considerably cheaper to get their french suppliers and installers to come over to the UK for a week, than to get UK firms to do it. The UK market is just too new for vineyard supplies.
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