JC Higgins scope mounts

I picked up a Sears/JC Higgins, Mod 50, 30-06 that had been sitting in the rack
at a local gun shop for quite some time. They were asking $385 for it so when
I was told I could have it for $200............
The problem I have is it has mounts already on it but I don't know what rings
fit the mounts. Looks like Weaver mounts but are too narrow for Weaver rings.
To wide for rimfire rings.
I ordered a set of Mauser 98 see-thru from Midway thinking that I could just
remove the mounts on the gun and problem solved. Not so. The mount holes
on the rifle are the same distance apart but on the see-thru's the holes in the rear
are closer together than the front. Front fits, rear don't.
I realy don't wont to drill and tap another hole in the rifle. There isn't enougth
room on the rear see-thru's to drill another hole in it to make it fit.
Any help please.... What rings will fit these mounts? I think they are like 9/16"
wide, and look like Weaver type.
Sears/JC Higgins Mod 50, Mauser action/Hi-standard barrel.
Thanks for any help.