For switches the Weatherdeck line from Blue Seas Systems is made for them by Carling Technologies. Best bang for the buck, can be found at most marine store, both brick and web. Blue Seas has excellent customer and tech support. Great discounts prices can be found online. Here is the Blue Sea line-up.
https://www.bluesea.com/products/cat...oggle_Switches
As far as the slop, some shifters had detente screws which may be adjusted, but it could well be that your shifting cable is shot, stretched, toast, etc.
Good luck with the new rig. You're gonna show-up some bad-as Farallons in that boat
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