Are you messing with us Super? IMR 4895 and H 4895 have nearly identical burn rates and their load data doesn't interchange. My burn rate chart (Lapua) lists Varget a bit slower than those two, and IMR 4064 a bit quicker.
A similar burn rate should indicate that the powder will also be suitable for that particular cartridge, but the powder volume or weight is usually very different.
Just as an example out of my Hornady manual, 338-06, 225gr bullet
H4895 Min load 39.5@2200fps, Max load 49.0gr@2600fps
IMR4895 Min load42.1gr@2200fps, Max load 53.0gr@2700fps
Varget Min load37.6gr @2200fps, Max load 51.4gr@2600fps
IMR4064 Min load42.9gr@2200fps, Max load 53.4gr@2700fps
All of these powders are fairly close in burn rates and all are suitable for this cartridge, however, as you can see, there is over 5gr difference in starting loads on this cartridge between Varget and 4064, 2grs exactly on max loads.
I load for 9.3x57 and I feel you pain here. Its not a wildcat, but there is no published load data for this cartridge ( at least not with powders available in North America).I'm not sure where to start to look for info on yours.
Jim