Your MMC is called just that - an MMC. Yun na mismo yung type niya. The 6600 was released way before the advent of SDs, microSDs, and miniSDs.
For your battery, MSM-HK replacement batteries are good replacements. About 150-200 per piece in your nearest tiangge.
Also, if I remember correctly, you bought a new laptop recently. That most probably has a built-in card reader. If it doesn't, CD-R King sells it for as low as 30 pesos each.