I would think that the House Navies would have better and more types of lvl 10 weapons than some other factions.
For example, the upcoming conflict between Liberty and Rhineland should be sending their respective R&D divisions into a frenzy developing as many high powered weapons as they can.
Kusari and Bretonia should have a few more by now due to the ongoing conflict.
As for the Outcasts and the Corsairs, I don't know how centralized their respective governments are, but I would think they would be developing some.
As for the smaller factions such as the LR, RHA, LWB, Mollies, Etc, I am unsure how much support they would have in the R&D end of things. Perhaps they stick with codies, or steal technology that was already designed.
Just my 2 cents.
Edit: The Lane Hackers prolly should have a couple more. They could have a decent R&D division, and the capability to steal new prototypes and design plans.
Formerly known as LPI Police Chief Hull O'Brien.
Creator of Sgt. V. Price, 207th Precinct out of Chula Vista Station