Try e-gunparts.com
HR is Harrington & Richardson. They first made guns in the US in 1871. The company changed structure several times, and is now part of Remington.
Somwhere between 1956 and 1985
IIRC early 70s
Need the serial number.
"M" prefix indicates 1952
Impossible to answer without the serial number.
This Model 676 was equipped from the factory with both a .22lr cylinder and a .22 wmrf cylinder - depending upon condition and barrel length (12" barrel commands a 20% premium) value will range from Excellent - $275 down to Fair - $75.
"C" prefix indicates 1942
Your H&R model 58 combo single shot rifle was made from 1975-1986.The letters AZ ahead of your serial number indicates that it was made in the year 1983.
I am showing that HR made a revolver in models 826,829,832,and 922.If you check your model number again it may be one of these.Please repost your question if that is the case.
1979