Actually, the 70HC (HC stands for High Capacity) came with a 20? or 25? round Ramline mag, back in the day.
Unfortunately, Ramline no longer makes that mag.
On the upside, Shooter's Ridge makes a 25-rd mag for the 795 that fits the 70HC perfectly

Downside of that is the first run early this year had some issues in the 795's...worked better in older guns like the 70HC/995/989M2.
Also pretty much required that you pillar-bed or regular bed a 795 for it to work...which is a good idea to add precision anyway
There also used to be a 13-rd steel mag that worked quite well with the 70/995/989 series...looks just like an OEM mag,
no markings...just longer. HARD to find, but very nice...my 989M2 came with one.