I'm a PA in Orthopaedic surgery and found your site while searching on casting cart brands. Hope you all don't mind my input on this topic.
As far as mobile carts, there is a good picture of one at http://www.lab-gear.biz/1461.html
. But you dont need to spend that kind of money on a stainless steel one. You can duplicate it with a good Black & Decker tool cart for much less.
As far as material, a lot of Ortho Surgeons do still like to use plaster, especially in the OR for splints...it's much more moldable than fiberglass.
Materials should include regular and fast drying types of plaster 2" to 6", of course have some fiberglass as well...webril both synthetic and regular in similar size ranges. Ace bandage both single and double length in various sizes.
We keep stockinette available but rarely if ever use it post-op.
Also the pre cut plaster sheets in various widths and lengths.
Some docs like to use a Robert Jones Splint in the lower extremity after an IM nail of the tibia..which is some webril on the skin covered with rolled cotton (split in half for easier application), covered by Kurlix for some compression then a posterior or stirrup splint of plaster. Some say to put the stirrup on before the cotton...user preference on that. The OR nurses where I work make a couple of bags of materials for the Jones dressing so they dont have to search around for the additional materials.
We keep a non-vacuum type cast cutter on the cart...it's more portable an easier to handle. We usually do any cast cutting in the pre-op area so there's no dust flying around the OR if we wind up doing an open procedure....and a vacuum won't cut down enough of it. But, that's user preference.
As far as plaster vs. fiberglass I would poll the surgeons you work with and find out their preferences. There's pro and con to both, The newer fiberglass is becoming more moldable and easier to manipulate.
Hope this was helpful