Bikbr2020 is correct. That book breaks down the complete forces of both sides.
Within the Watchman Galaxy's 48th Battle Cluster there was a ProtoMech Binary.
ProtoMech Binary
Alpha Star
Minotaur
Gorgon
Roc
Hydra
Satyr
Bravo Star
Harpy
Siren
Centaur
Roc
Hydra
Then in the Iron Guard Galaxy's 33rd Assault Cluster it lists the exact same ProtoMech unit in name and composition as listed above, they are identical. Very copy/paste to me.
I will say it just lists 1 ProtoMech type for each Point. And we know that Protos can mix and match in points. So I'm not sure what to do with that. Maybe at the time of publication it was conceived that protomech points would be pure, 1 model only. Like a point of BA.
I think if I was going to use that to build a unit today. I'd imagine each Star as having a Point's worth of those machines. For example in Alpha Star. I'd conceive of it as having 5 Minotaurs (total, across the Star), and 5 Gorgons (total, across the Star) and on through the whole list. Then I'd mix and match to create actual points that better fit what I wanted.
EDIT: I see now in Scenario 4 of Twilight of the Clans, ProtoMechs are part of the Clan force in the following composition.
Binary ProtoMech, Alpha Star
Point 1: 2 Harpies, Gorgon, 2 Minotaurs
Point 2: 2 Centaurs, Roc, 2 Gorgons
Point 3: 5 Rocs
Point 4: 2 Hydras, 2 Rocs, Gorgon
Point 5: 3 Sirens, 2 Satyrs
There's another mixed Star of Protos in Scenario 5, not exactly the same. I don't have time to copy that one. If you really want it, say so and I can circle back to this. But I think it serves to answer the question. I think you wanted to know many Protos you were, there were 4 stars worth of them, of virtually or literally all the Generation 1 models that were introduced in TRO: 3060.