An interesting option would be to look at the Accuracy International or CDiPrecision removable magazines for M98 rifles, some of the mags are supposed to hold 3.60 inch rounds. Bottom metal and mag aren't cheap but are a bit less than good H&H length bottom metal.
http://www.cdiprecisiongunworksstore.com/mauser-98-large-ring-magnum-magazine-dbm-remington-798/No first hand knowledge of these so, as always, do your research.
