When I was looking for a 42" for my Husqvarnas, all I could seem to find in 3/8 was .063.
I see the Logosol is currently out of stock. Bailey's sells WP (rebadged Cannon) and Cannon, but don't list the size you are looking for. They may be able to order it. Cannon's website indicates the bars can be made in all gauges, pitches, and lengths.
If you're currently running 3/8 lopro/picco, then maybe I could see the point. If not, a few loops of 3/8 .063 dedicated to a 42" shouldn't be a source of confusion. BTW, I bought my 42" with a loop of ripping chain for 1/2 the price of that Logosol bar.