I have that same rifle, 375H&H Interarms Whitworth Express Rifle.My Pre 64 Model 70 Alaskan in 338 win mag. My dad bought it new at Reeds Sporting on Main Street In Kalispell. My dad , brother and I have all killed elk with it.
I have one rifle that I did sale that I really regret. It was an Interarms Mark X in 375 H&H mag. That gun was a shooter. Loved shooting it with open sights. It had a three leaf folding rear sight for 100 , 200 and300 yards. My wife was looking at some older pictures recently. She handed me one of her dad holding that rifle. I was a fool all over again.
owned for 40+ years. Performed to perfection with everything from Impala to Cape Buffalo on trips to Africa in my younger days. Beautifully made and exceptionally accurate.
300 yard Okavango Kudu …a long shot for me in those days….Too many memories to consider selling it.