Did Omega (or anyone else) ever make pulsometer bezels for the 3520 Day-Date? I'd think that would be slightly more useful than a tachymeter, and it'd look neat. In the same vein, does anyone know of any modifications or replacements bezels for a rotating dive-style or friction bezel replacement, or anything like that? Sacrilege, I know, but I'm curious to look, at least.