Shep: I think the original switches (for the later cars) might have been from Bertone/Lucas. Oddly, I did run across such an item a while ago on Ebay. I did not buy it, as it was not correct for my car. Here's something similar - a lucas window switch for Ferrari:
http://www.ebay.com/itm/Ferrari-Maserati-Switch-Lucas-Window-OEM-/160672835246?hash=item2568d8e6ae&item=160672835246&pt=Vintage_Car_Truck_Parts_Accessories&vxp=mtr Here (below) is a current replacement rocker-type window switch for Bertone/ducellier. As you may remember, Emmanuel discovered an exact, bolt-in replacement for his window lift motor and armature unit, sourced from Maserati parts (Indy, I think). They (Maserati) also used Bertone window lift switches. Here are links to the modern replacements, sold through Maserati club international (MCI) (I don't know if they are identical; they appear to be, but....
http://www.maseratinet.com//pc-10700-371-window-switch.aspx http://www.maseratinet.com//pc-10700-551-window-switch.aspx http://www.maseratinet.com//pc-22475-441-chrome-switch-frame.aspx Here is an "alternate" bertone replacement switch:
http://www.maseratinet.com//p-10687-window-switch-bosch.aspx These are not "American" switches - No doubt they were made in Europe (or China, or somewhere) can be purchased in Europe or the UK. Possibly they may be seen and measured "in person" to determine if they look and fit as per the originals.
As you know, what is "right" depends on whether your car is an early or late car. The late cars used rocker-type switches. My early car had a lever-type window switch. At least, that's what was fitted when the car came to me. I found some old Lucas window switches that look to be the same as those I have now. (of course, I can't find them at the moment. They've been stashed somewhere). These require a surround for mounting (as is fitted to my present window switches). Here's a link to the (possible) similar lucas switch:
http://www.ebay.com/itm/140497720077?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649 I have not changed my existing window switches, as they still work well. Unfortunately, the rubber boots that covered the lever (when I got my car) have perished. I don't know if they were "original", but they were certainly "old" and torn.
As a side-note, MCI have the small, circular decals for identifying the function of early-type 428 dash switches.
http://www.maseratinet.com//p-10137-switch-emblem-decals.aspx Those same switches were also used by Maserati as well as Monteverdi, Rover (and others). I have purchased several original in-the-box two and three position dash switches over the years as spares. (they too, are stashed somewhere - don't know where).Here is a similar early-type dash switch on Ebay.
http://www.ebay.com/itm/MASERATI-MISTRAL-GHIBLI-LAMBORGHINI-400-LIGHT-SWITCH-/120759448421?hash=item1c1dd2f365&item=120759448421&pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr Emmanuel has a trove of rocker-type dash switches, I believe sent him from Australia. Ahhhh the Interwebby-thing! So useful for finding the "impossible-to-find"!
Sorry; None of the above has anything to do with seat belts. But they could possibly be useful for the 428 parts list, of which Andy is the curator, in addition to his many voluntary club duties.