Talk to Jason (Alfissimo). He has spent some time researching this.
Usually, people look for used struts from B/L/LS if replacements are needed, or if you get a set of used struts from the S/Q, you can use them. They will remain in the default "sport" setting since you will have no wiring for them to open the softer ride valves. No big deal, esp if you are looking for a sportier shock, since I run my 91S in that setting full time. My wife and I prefer it that way.
The advantage of the used S/Q shocks is that they CAN be rebuilt by yourself, involving using a new (but not that expensive) machined seal carrier, and new inexpensive seals, and of course new fluid, as compared to the others. I've rebuilt mine, and they work fine. Cost several hundred or more to rebuild them, depending on whether or not you have to have the rods rechromed, but I was lucky and did not. Richard2 did when he rebuilt his, and that ended up costing him a bit more. There is a PDF file available on the BB with all the info required, complete with some pictures of the work.
In any event, the shocks for these cars do last one heck of a long time anyway. The ones on my 91S were still pretty good at 180k miles, except one stopped working properly even If it had fluid in it. Repairing it made it work fine again (at least I think that is what happened, lol).
One thing to look for with used shocks is that you have to watch for severe rust bulging between the tube and the welded on wrap around mounting flange at the bottom. Cars which have been run in areas of salt on the road will have that corrosion, and if not terrible, can be treated with a lot of rust killer solution and then painted with a few coats of rust prevention paint.
89 Milano (wife's daily driver since 1989, Shankle Sport)
91 164S (my daily driver since 1994)
94 164LS (~Q) (trip Alfa since 2000)
72 Morgan 27 (water time since 1976)
previously owned since 1964:
62 Morris MiniMinor 850, 67 Austin 1275 Cooper S (Downton 3/4 race), 64 Giulia Sprint GT (1st red one made), 72 Fiat 128 Sedan, 75 Alfetta Sedan, 78 Alfetta Sedan, 78 GTV, 81 GTV6, 86 GTV6
Last edited by Del; 03-10-2017 at 10:32 PM.