Ripcord, as said before the bonnie hat with skull is from a cavalry unit called Lusitania, otherway the bonnie hat with Legion embroided emblem is a correct one used in Legion.
About the parka....that model was a common model used for all the ET (Ejercito de Tierra), incluiding Legion forces, the most difference you can find is the removable shoulder straps that were used by Legion members who paid them from their pockets and that although weren´t official ones were used by everybody.
Unfortunately have to say that there were no sniper units in Legion, of course there are snipers, companies use to improve in a snipering qualification to best shooters who have to do their expert shooting course in 2 different modalities depending the qualification. 7.62 NATO (accurazy) and 12.70 (Barret). Most snipers are 7.62 and there is a limited number in companies but they are not a special unit at all.
Snipers act like common personal diferencing the tactics when they have to act like snipers, of course they have their training apart for not being obsolete in long range shooting.
That parka is no different to any other army units in a vintage obsolete camo pattern.