The original nozzle reads: .60 (gal/min) and 80 B (degrees). Can I use a .65 and 80ES nozzle on my kerosene fueld Miller Mobile Home Furnace?

If you have the proper knowledge to set up a different nozzle it might be OK.
For most people it is best to stick with what is on the rate plate. A .65 will burn more fuel than a .60 and may over fire the furnace making it not last as long. This is why I do not recommend a home owner up size the nozzle.

Also the 80 degree spread should have the same designation. The B and ES means two different things as it could be a solid ,hollow, all purpose flame spread an you want to maintain what the factory recommends because it can boom or do other things like burn the sides/plate on the heat exchanger if not correct.

If you do not know what you are doing on oil call a pro. Just having the furnace adjusted a bit wrong can cost you big $$$$ in wasted oil due to improper burning in chamber.