I agree that this looks like a 2300 engine. Tony Stevens of AlfaStop in the UK has some for sale too (scroll down this page, then click on the red 'Info' button below the "2300cc RIO engines, PRIVATE SALE" item to go to a separate page with links to some pictures).
What do you intend to do with the engine? It is a very close relative of the 00204 engine found in the 102 cars, but there are some significant differences.
I've battled with my FNM and seem to have it working OK now. I don't have an FNM transmission, but the FNM engine mates directly to the original 102 transmission. I note that the transmission in the picture has the rear trans mount at the lower rear much like the later 105/115 models, so if you plan to put this into a 102 car you'll need to use the holes in the bell housing for the dual rubber mounts that go there for the 102 cars. I'm guessing you could leave the FNM shift tower in place and just ignore the mount at the bottom.
I see it has the alternator mounted at the lower right front, but is missing the rather massive bracket that mounts on the left to hold the power steering pump, and I think the AC compressor. I had thought that the compressor mounted on the lower right and the alternator on the left, but did not get these components with my engine.
You are missing the intake manifold, and I strongly encourage you to get one and mount a pair of Webers, or even the original 40 ADDH Solex instead of the 102 manifold and 44PHH carbs.
The FNM uses a 3-groove crank pully to drive all of the modern accessories on the front. I'm not certain these will clear the radiator in a 102, but suspect they will. I used a 102 single-groove crank pulley and 102 water pump (so the grooves would line up) and mounted an original generator on the left side per the 102 configuration.
If you intend to mount the engine in a 102 roadster you have to remove the oil-filler snorkel from the left forward cam cover. Not a big problem if you have access to a good machinist and welder. You'll then need to fabricate a filler that bolts onto one of the plated galleries on the front.