Zoom H1 sound recorder is the must for making videos with the DSLR. The only disadvatnage, it records also all handling noise. All shock mounts you can find are so bulky, that question will arise - Why I needed small sound recorder and big mount for it? Good reason for another DIY project. Needed are Velcro fasteners and double sided cable sleeves you can order here. You need 25x2 mm metal plate (your old ruler) and 2 standard camera screws also.

Velcro and cable sleeves you can order here. Look at my video, what to consider and how to make it