Yeah well that 12 lead from Allyn is close to $2500 which is a pretty penny especially since dept not only wants you to know but also to be able to treat and pacing/cardioversion is not available on those units.

I know that about 2 years ago there was a company that had a semi-manual defib about the size of the video tape but I think all the units got recalled due to battery issue.

An English company makes a product available on the market now that allows you to put a unit (size of two decks of cards) in pts hands and ask them to hold two electrodes with their thumb. You get a a display in one lead with machine calculated intevals. Interesting but not FDA approved which makes it useless as diagnostic tool in clinical settings. Those units are available on ebay for about $250.
http://dailycare.en.ec21.com/GC00976239/CA00976240/ReadMyHeart_-_Handheld_ECG_Recording_Device.html

Well it seems that FDA is interested in this unit and here's the paperwork:
http://www.fda.gov/cdrh/pdf4/K042814.pdf