The original screws weren't 2BA, they were 3/16" Cycle (32TPI) but 2BA is close although a slightly looser fit and commonly supplied by eBay suppliers as being correct.
I have found that UNF 10-32 is a much better fit and is available in stainless and fillester head so are a great replacement that doesn't need any damage by tapping to something else.
UNF is a 60 degree thread form so is a very good match to the original 60 degree Cycle and despite the specification for 10-32 UNF being a couple of thousandths of an inch bigger in diameter to 3/16" Cycle, in practice with manufacturing tolerances I have found them an almost perfect fit.
I have seen them at aircraft suppliers but I got mine from McMaster-Carr in the US (1/2", 10-32 UNF Fillester Head, Stainless) - part number 90280A829L.
