I carried a 659 in the early 90's as a LE duty gun. Back then we were still issued revolvers until we transitioned to Glock's in 1993 so with having to purchase our own semi-auto's, I didn't hesitate to buy a 659. I loved my 659 and always regretted selling it but mine, like yours was an adjustable sight model and I always wanted a fixed sight model. At the time night sights were relatively new and the only way to get them on a 659 (back then) was to have a fix sight model. However, it fed, functioned and fired flawlessly. It was a tad heavy but it was just something we lived with. I have often considered replacing mine with another but I usually don't see them for sale for less than 400.00 so your price of 330.00 was an excellent deal, especially for one in that condition.
Nice find.