Here is what I see from the seven images:
Figure 1 shows a non-original manufacturer's identification plate. I don't see any value in this information to answer your questions.
Figure 2 shows what perhaps might be an original hull identification plate but now obscured. I don't see any value in this information to answer your questions. If you could very carefully remove the paint or gel coat that is atop the plate, you might find more information that could identify the year of manufacture.
Figure 3 shows what appears to be a stencil number, which can be useful in identification. The sequence 3E
nnnn suggests that this hull was a 16/17 foot hull. The 3E prefix suggests the boat was made sometime after 1972, but nothing further can be inferred from this number without consulting with Boston Whaler archives. However, recently the customer service department at Boston Whaler no longer offers callers information from those archives, if the archives themselves still exist.
Figure 4 shows the transom on Starboard side. The cleat is not OEM. The swim ladder is not OEM. There are odd rectangles of what appears to be different color gel coat [but on further study the strong sunlight has created shadows of the swim ladder which cause the gel coat appearance to change due to the lighting]. I don't see any value in this information to answer your questions, other than the weight of swim ladder would not be included in any weight provided by Boston Whaler.
Figure 5 shows the boat has a non-OEM cleat at the bow centerline, not the distinctive Boston Whaler navigation lamp-chock assembly. The boat has a reversible pilot seat, which was often seen on a MONTAUK. The decals on the hull sides are not in proportion to the original decals. The engine remote controls are mounted to the port side of the center console, which is very non-OEM style. The RPS has a teak seat back. In later models (such as 1991 30th Anniversary MONTAUK 17 model) the RPS had a laminated molded seat back.
Figure 6 shows the boat from the Starboard bow quarter. The bow cleat is also seen in this view. The navigation lamps are attached to the center console, again not in accordance with the original design. The hull has the bow smirk design. This indicates the hull was molded in 1976 or later. The console has an odd two-tone gelcoat color, which is very unusual [but on further study, the cause of the apparent console gel coat change is due to the windshield having a dark tint, and that changes the color of the gel coat under the windshield]. The typical Boston Whaler center console did not have completely flush-with-the deck bottom edges, but had reliefs so that deck water could flow through the console. Compare with
several images in the REFERENCE article.
Figure 7 shows the cockpit from ahead. The anchor locker hatch is a different color than the hull, which suggests the hatch is not the original hatch, which could have been made from wood, or could have been a molded laminated hatch. But if the original hatch were a molded laminated hatch, there would not be a need to replace it with a new hatch. The original hatch was probably wood, and it was likely abandoned and replaced with a new hatch made from some synthetic material whose color did not match the hull gel coat. The side railings are seen in detail. These railing are the welded railings used in later models, where the horizontal railing is attached to the vertical railings by welds, not by mechanical fasteners. This suggests the railings are from some time newer than 1979.
Conclusion: about all that can be learned from the photographs is the hull was made sometime after 1976 and the railings were made sometime after 1979. The boat is not an actual MONTAUK model, but it does have several elements of the MONTAUK model, such as a center console, RPS, and railings. The weight cannot be deduced from the photographs. Among the weights listed in the REFERENCE article on the 16/17 foot hull, the 950-lbs weight for a MONTAUK 17 in 1999 would probably be the closest approximation.
The boat appears to be in nice condition, and the newer four-stroke-power-cycle engine should provide very good propulsion. But establishing its exact year of original manufacture to be a precise year is not possible, at least not by my interpretation.
Perhaps other readers can offer additional insights into the year of manufacture based on the seven photographs provided.