Thanks Peter
I did get some of the Heavy Cavalry (armoured horse) and Generals from Casting Room and they are nice sculpts. Have also used other companies' 28mm figures - Battlestandard (US firm), Essex, Sgt Major, Tin Soldier, Warlord and Wargames Factory (plastic).
Wargames Factory have plastic Persian infantry sprues at a very good price - maybe not the best figures in the world but a good size and can be Kardakes, Takabara and bowmen. With the old fashioned spara they could also act as levies in the later period. After a coat of paint they are fine.
Good luck
Garry