Sir TR,
This was a popular fishermans friend when fishing Alaska rivers where the Brown Bears may be about...
These were available in the PX @ Ft Richardson, and not expensive in 1978.
http://www.gunblast.com/Hamm_44-Flattop.htm
The September 1, 1956 Distributor price sheets listed the new Blackhawk .44 Magnum with a suggested retail price of $96.00
RUGER .44 Cal. BLACKHAWK “FLATTOP”
The four major types of the Ruger Blackhawk .44 Magnum “Flattop” are listed below:
Type 1 - Standard “dull” polish blue finish, long throw offset-slot ejector rod housing, small square serrated ejector rod button, checkered black hard rubber or varnished smooth walnut grips, and 6-1/2” barrel. Estimated about 100 made.
Type 2 – The ejector rod button was changed to a large concave faced or “dimpled” button. A very few early guns had checkered black hard rubber grips but the very large majority had varnished smooth walnut grips. About 10,500 made (includes about 2,500 estimated sub-Type 2a guns with the wide land Single-Six type cylinder base pin tip).
Type 3 – The cylinder base pin had a “collar” added to keep it from exiting the gun from recoil when firing. About 5,000 made.
Type 4 – The ejector rod housing slot was straightened. Also the ejector rod button was changed to a flat faced button early in this type’s production. The 7-1/2” and 10” barrels were also introduced as Type 4s. About 14,000 total Type 4s made