I would agree... a 1965 would not have hyd front assist from the factory. That option came in '69 with the console changes.
If I'm not mistaken, the console tractors did not have the weep holes in block, either... but I could be wrong on that.
Coolant weeping from the hole means that one of the o-rings on the piston sleeve is leaking. Keep a close eye on the crankcase oil. If it shows signs of coolant, you need an engine overhaul.
Good luck. Some pictures would help us determine if your front assist is original or not.