If you mean an SD card Secure Digital ( flash memory ) , not SDRAM ( Synchronous dynamic RAM)( as applies to a PC memory ) I fear your title may confuse as they are quite different components
Did you see
>£200 camcorder, SD card, good battery ??
£200- 300 will get you only a Standard Definition model, although some 720p Hi def models exist but are generally not universally popular or mainstream , as such
Image quality and audio quality will reflect the price point which although is decent money, in Camcorder terms is entry level
Canon makes the FS 100 , Panasonic the S7 These record Mpeg2 to SD/SDHC card and will not set your pulse racing in lower light
Panasonic actually has a range of these camcorders , the S150. S9 ect but Im not sufficiently familiar with them to comment on performance
Samsungs MX20 uses H.264 which is even more compressed and is great in its own right but is not an absolute video quality award winner ( See thread in the Stickys in this forum )
Sanyos Xacti model also record mpeg4 to SD card .. They seem to be marketed as lifestyle products though as they have still ability and are almost universally small enough to slip into a pocket
Canon FS 100 has a thread and mentioned in several threads here but the consensus is that it struggles in low light
Toshiba Camelio is an SD card model that is not very well endowed but is cute and very pocketable.. You can give it a miss with your budget
Im not sure the audio quality varies widely