I am 53, and wear progressive lenses on dry land. About 4 years ago, I bought a prescription bifocal mask from these guys:
SeaVisionUSA
I was a little hesitant to plunk down the $$ for a mask that I had not tried on first, but went with one of their recommended masks for "most face types" and it has worked like a charm. A lot of dive shops also stock Sea Vision masks, in case you want to try one before you buy.
It's definitely become my favorite piece of dive gear, and the only one that is truly essential to travel with. I see with crystal clarity underwater, and am a much better navigator and spotter of marine life than I used to be, and I can read my gauges comfortably. The only drawbacks are (1) the correction for distance vision works perfectly underwater, but not above water, so when you come to the surface, your vision won't be as sharp; I see about as crappily without any distance correction as with the mask on above water; and (2) when using a bifocal mask, there is some range (for me, around 4 feet) where you find yourself toggling between the readers and the distance part of the mask, which takes a little getting used to.
The only other advice I have is that the defog solution that comes with the mask is awesome. I have used plenty of other defog solutions and none have worked as well. I normally am a real cheapskate and would just go with diluted detergent in a recycled bottle, but whatever they put in their proprietary defog solution really makes a difference.