I bought a pair of Dewalt wrap around tinted safety glasses with a magnification diopter molded into the lens
.You can select
a bifocal length of 1.5, 2.0 or 2.5. Cost was less than $12.00 from SafetyglassesUSA.com. They do the trick for me.
http://www.safetyglassesusa.com/bf16.html