7.6 was an interesting beast; each build had its own licensing agreements with those whose software was bundled on the disk. I believe these bundlings were regional, which resulted in regional CDs being pressed.

By the time 7.6.1 came out, Apple had straightened out their licensing, and didn't have a bunch of the regional bundles included in the update, so they were able to make a full international update available.

As a result, you'll likely need to get one of the bundled Finnish installers to get the original 7.6 -- but this was an extremely small run, as 7.5.5 came out in November 1996, 7.6.0 came out in January 1997, 7.6.1 came out in April 1997, and 8.0 came out in July 1997.

Many computers were sold with 7.5.3 bundled right up until they started bundling 8.0.