Different powders for the 6 & 6.5 CM's ?

[Baddog 0302]

ALL of the "standard" powders for the 6 & 6.5 CM are not to be had anywhere. As alternatives has anyone used Norma 204, or VVN 550 or 555 ?
And if you have , any problems using SRP's {7 1/2 of 205M}