| Actually, it's not too hard to get a straitjacket, though their actual use in asylums is in decline. (So much more humane to give them neuroleptics instead...) Posey, a medical supply house doesn't like to deal with BDSM fans, which is a shame, since most consumers state that they have the most comfortable standard-make SJ's around. Humane Restraints, which supplies prisons as well as psychiatric institutions, and has all sorts of gear to immobilize people, carries two models, one specially gimmicked for escape artists, however, their take on the SJ has an uncomfortable ridge near the neck. (Oddly for them, since even a vanilla cream puff like me can see how much trouble they take with padding and lambswool otherwise...) Expect to pay $250-$300 USD for a new standard canvas model...leather can go into the thousands.
Pretty much the Cadillacs of the SJ world are those made for the escape artist and bondage trade by "Dr. Mad Max" Cita. Taking up where Posey left off (his "Trainer" model is a Posey clone), his line includes "The Protector", the "Psycho", and the dread "Psycho-X", which add various safeguards and custom-fit to the classic model. He also carries "The Boot", a leg restraint, as a complimentary piece. He claims that all his models are comfortable enough to sleep in!
Strapping someone in is a delicate operation, even if your subject is cooperative: it should be snug, not tight, and the crotch stap used. (I'd put a Depends or similar on, just for added padding.) The sleeves should be adjusted asymmetrically, so that the bottom hand isn't under the elbow, and the top strap used (to minimize fatigue at the shoulders). If you have to walk with one on, it's a good thing to have someone with you, hovering somewhere near the projecting elbow: a person in a SJ is topheavy and somewhat unstable (pun not intended), and it's very, very easy to fall when you can't use your arms to balance. Tough to get up, too. Also, they can deal with things like door handles and the like, and get you drinks (with a straw) as well as adding to the general "atmosphere".
My own experience with this, oddly enough, comes from a Vivienne Westwood blouse that differed from a real SJ in that it was gauze (but hard enough to tear, believe me), and had open-ended sleeves and shoulder D-rings so that you could pull them up and actually wear it as a blouse. However (hehehehehehehe) you could turn the sleeves out and wrap twice around the waist....It was fun to get unwrapped! | 
