Skippy, O1 is readily available, but one of the characteristics of it are that to get the MOST out of it, it needs to be held in the 1500 degree range for longer "soak" times than the simpler steels, like 1084.
"Simpler" means that they do NOT have the additional alloying ingredients like O1 that make for the longer soak times.
Some people even hold it in that range for as long as 20-30 minutes!
This, of course, requires heat treating ovens or similar equipment with some type of refined temperature control.
1095 works great with the proper quenchant, without the long, extended soak times.
Look around for some 1084 - you'll find it!