Just to be clear, you have a BX23S which is a world away from a BX23 which was manufactured in the early 2000s. Make sure you bring a picture of the tractor VIN with you when picking up supplies from your local Kubota dealer. Filters from the dealer don't cost any more, and keep your Kubota all Kubota. For engine oil, I would suggest Shell Rotella T6 Full Synthetic 15W-40 Diesel Engine Oil. You might also consider having an engine block heater installed, or do it yourself for easier starting in the cold Connecticut weather. I am also in CT and my block heater has been a definite improvement for quick starting when the temperatures drop to the freezing point. Also, check the anti-freeze is full strength so you don't wind up with a frozen engine block.
.