Exterior or interior?
If it's interior I'd probably just use Ben Moore "Advance" waterborne Alkyd.
Roll on, brush out to get the best finish. Takes too long to apply with just a brush.
For exterior, you have a few choices:
cheapest would be a can of Oil Rustoleum. Not the greatest paint but will do the job.
Next up in price would be a polyurethane enamel like Duron's "Duraclad". I've had this on my black front door for 16 years, but for sun fading it needs to be sanded down and recoated every two years.
If there's little sun exposure it is a great choice.
Finally, if you want the best finish available, there is "Hollandlac Brilliant" from Fine Paints of Europe, but you'll need $60/qt. to swing it. Applied over their "brushing putty" undercoat, there is nothing shinier or more luxurious-looking.