These pilot notes might be of interest
https://washingtonseaplanepilots.org...Beaver-POH.pdf
A quick read through does highlight that the ASI goes up to 250 MPH (?) VNO is 180mph normal max speed is 145 mph at sea level but the normal flight envelope is between getting airborne a 55 -65 mph with T/O flaps and climbing at 80 to 95mph with climb flaps. The area of normal operation on the ASI is only about a quarter of the indicator and very compressed at the T/O and climb section.
Referring to the stall (60 mph clean zero bank) the manual states "the stall is gentle at all normal conditions of load and flap and may be anticipated by a slight vibration that increases as flap is lowered. the aircraft will pitch if no yaw is present. If yaw is permitted there is a tendency to roll. Prompt corrective action must be initiated to prevent the roll from developing.
Instruments like the ASI might well have been updated since then.