We tried a few wines from Rookery Wines. They charge for the tasting, $1 per small splash in a cup (non-payable if you purchase a bottle).
We tried three wines including the 2003 Cab Sav and the 2004 Rookery Red. Looking at their website these are their two cheapest wines and tasting them did the winery no justice. If you are going to charge $1 a splash for a $12 and $14 bottle of wine, that was both oxidised and well past it's prime you really can't expect much in the way of any cellar door sales.
My advice, if you wanted it, would be to bring out some more recent vintages that were not past their prime. Choose some of your better wines to showcase in the paid-for tasting (I am assuming that the wines in the $20-$30 category fit this bill). I do understand that you are left with the problem of what to do with the old vintages but as I said, having people try that old and oxidised stuff will just see you moving through the old vintages $1 sip at a time.