Okay what I'm sure of is
1. Murmillones
- low leg greaves
- large oblong shield
- sword
2. Retiarii
- trident
- dagger
- net
3. Hoplomachi
- small round shield
- high leg greaves
- spear
That leaves dorsal helmet, sickle, padded shin guards, talon helmet, and shoulder guard.
Dorsal helmet: While I can't find anything particularly telling, the Murmillones are said to have worn a helmet (of the Cassis Crista type, according to wiki) with a stylized fish on the crest. The images I get from that seem pretty dorsal fin-like to me. And the Retiarii don't wear helmets.
Sickle: The Retiarii are based on fishermen, the Murmillones on soldiers, the Hoplomachi on the militia. While that makes the Hoplomachi most likely to end up using a sickle, I find no evidence that states they indeed did use it. So this one belongs to none of them.
Padded shin guards: The Hoplomachi and Murmillones have greaves. It is not mentioned anywhere I can see that the Retiarii wore shin guards, but looking at some of the art from the time it seems they have light armor on the shins.
Talon helmet: If we attribute the dorsal helmet to the Murmillones, the Talon helmet must either belong to the Hoplomachi or none of them, as of the Retiarius it is said, "he wore no head protection or footwear." The Hoplomachi are said to have a bronze helmet, but of what type? It is a mystery. I don't know what either of these helmets are supposed to look like btw? The terminology used is giving me NOTHING.
Shoulder guard: While the Murmillo arsenal mentions an armguard (manica) that extends the length of the arm and covers the shoulder, the Retiarius is very specifically given a "shoulder shield", a galerus. So for wording's sake, I'd give the shoulder guard to the Retiarii.
lol wow lot of posts are i was researching but hey thats what i got man