I hope it is not to late already!
If you have access to a water hose get a set of muffs and run the engine with the tap water until it is at operating temp, that way the thermostat is open! Attach another short pc. of hose to the muffs after removing the tap water hose from the muffs and use a funnel in the open end of the short pc and pour the pink antifreeze in the funnel while idling your engine the water pump will pick up the antifreeze and pump it thru the engine! I use 5 gallon and that should be enough to get the job done. The anti freeze will come out the exhaust ports at the bell housing and thru the prop.

You could try Dubberts Professional Outdrive on the east side of Port Clinton as they are open all winter. Here is there number 419-732-1777.

I don't relish the thought of bringing you morbid thoughts but You are in a pickle as the weather is against you. You could also take off the thermostat housing and pour antifreeze into the engine that way but you need to get it done as soon as possible. What ever way you decide to do it get it done as soon as possible. If your boat is stored outside You may already have suffered extensive freeze damage to your power train unless the block has been drained. Best of luck Wakina.