My guess would be a set of 45 & 46s
That might be a good guess, but Schulz & Larsen rifles were built on a variety of actions, most notably the Mauser 98k action. Schulz & Larsen is a Danish company, so hole spacing will be metric, and the correct mounts may be similar to the old Husqvarna Crown model rifles.
BTW, Shulz & Larsen is still in business. Nice rifles.