There are two main upside down blades, th eAustrian 1895 distiguishable by the two proud rivets on the cross guard and the Czechicon 23/24/33 series that look like Germanicon 84/98's but with 3 blade lengths. Take a look at
CZECHOSLOVAK Mauser Bayonets and Variations
there are most variations there (bar a non mountable dress that i keep gettign their after "I just sold one" )