When I talked to MS yesterday - they kinda said - they can order it for me. However, they could not give the $ figure.. May be I should try calling TK or some other shops today..
IIRC, I saw it at Orient Photo at Sim Lim Square and TK Foto.
I've also tried to buy some Tamrac stuff from MS Color Ang Mo Kio. However, they seem not interested in getting the Tamrac stuff for me and in the end I bought it from Orient Photo.