More economical solution is to buy them bulk depending how many you need. Check ebay some sellers sell them by the lot of 4 or 6 or sometimes more. Few of us got together and purchased 28 of them from ebay had no issues. Just make sure holder has the drain on the bottom and it is marine grade or rated for outdoors. Good luck!
2007 X1 - Midnight Black/Viper Red
1996 ProStar 190