Changes to the 65 over time were minimal. Per the VAG link above, I sorta divide the 65 into three generations, mostly distinguished by the frame casting and sights.
+ "Gen 1:" Rounded front sight housing with fixed integral blade, recessed lettering, short tang, and a short rear sight with interchangeable blades for different notch widths.
+ "Gen 2:" Rounded front sight with interchangeable blade inserts, embossed lettering, short tang, and a longer rear sight with cam-adjusted notch width.
+ "Gen 3:" Angular front sight housing, embossed lettering, long tang, and a wider cammed rear sight. Both sights were shared with the model 80.
The 65's standard grips were actually sport type ones in checkered
plastic. Wood sport grips (early checkered, later stippled) and match grips (in two subtly different styles, made in different sizes, and left and right-handed) were all
optional upgrades. The nice tapered blued barrel sleeve was also an
optional fitting.
Beeman's US marketing of the 65 caused some confusion:
1. He always pushed the match grips. Wood sport grips were a pricey option only. He never even illustrated the basic plastic ones.
2. The accessories offered varied over time..sleeve and clamp-type barrel weights, sport grips came and went.
3. Introduced the "Gen 3" gun in 1981. Long barrel now called the "Mark 1." Shorty "Mark 2" arrived in 1982. These were
not factory designations. Beeman implied the short barrel was new, but it had been available in Europe all along.
4. In the late 1990's (after Dr. Beeman sold the company), the LONG barrel suddenly became the "Mark 2" as they cleaned out the warehouse!
The OP's gun is a textbook "Gen 2," with standard barrel, barrel sleeve, and match grips.
To supplement the VAG pics, here are my two: right, "Gen 2" standard 65 with barrel sleeve and match grips; left, "Gen 3" with short barrel and sport grips. Note the differing sights and tang length in particular.
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