Macro lenses have some advantages:
- they are very sharp and render a lot of detail
- they allow close focusing. Maybe you don't need 1:1 magnification, but you can still go down to 1:2 or 1:3. Most non-macro primes allow only around 1:7, which can be limiting with product photography
- they have a flat field of focus and a generally "sterile" style of rendering. This means the character of the lens doesn't take attention away from the product
- they tend to have good distance and DoF scales, which can help you out a lot.
So your options are to use a regular prime and crop the photo if needed. Or buy a new prime and frame it as you want. The
DA 35mm f2.8 ltd macro is very beloved, even in the non-macro range. The
DFA 50mm f2.8 is also hailed as one of the sharpest 50mm lenses Pentax ever made. The DFA 100mm is also a great lens. The third option is to save some money and buy one of the older macro lenses, maybe even an A or M series lens. You lose autofocus and such features, but the image quality will still be pretty great, and you get good closeups. Some older macro lenses only go down to 1:4 or 1:2 and need extension tubes to go beyond, but you probably won't need that. OH and btw, a lot of modern zoom lenses claim to be "macro" but they rarely go down to 1:4 magnification and their IQ definitely won't be on the same level as a dedicated macro prime.
One thing to keep in mind is that its not all about the lens. With product photography its a whole setup. Lights and background are key. You might need to use focus stacking to get the whole object perfectly sharp. And post processing is important, too. Then there is the whole aspect of trickery, things like making the object appear bigger or smaller than it is, or adding things to make it more appealing, like a polish or something. These things can even ruin the product, but it would look better in the advertisement and sell more units, so its done anyway. This, of course, cannot be done to unique items.
Just think about the photo you posted. To make a deep dark background, a reflection that doesn't reflect lights or camera gear, photo that is sharp but not overwhelmingly so, the watch is lit from different sides and looks great, etc. Its a whole art. Best to read up on it a little.