I have no source for those and wish I did... locally...
I have been eyeing the local cdrking and found this.. very tempted on my last few visits there:
Reads the folloing format of ebooks: TXT, PDF, EPUB, FB2Also suports:
Audio: MP3, WMA, OGG, APE, FLAC, AAC, WAV, AC3
Image: JPG, JPEG, BMP, GIF, support scale photo viewing, support lantern slide
Video: MKV, AVI, RM, RMVB, MP4, MOV, VOB, DAT, FLV, 3GP, Support H.264 code
Support: 720P video player
Flash: 2G
Card Reader: TF Card, up to 16GB

NOTE: Not nearly as good for ebook reading as the western products but this is a readily available local alternative if you have no other choice.
7\" version 4k
5\" version 3k pesos