Hi Carolyn,
Although in an ideal world collections might only ever have contact with the most stable support materials, for the short-term use you describe I don't think I'd prioritize it as the cost difference is likely higher than the potential benefits. As you mention, though, the wear and tear from handling is a separate issue and I would prioritize choosing the forms that will allow the garments to be put on and removed most safely during photography. I would also be careful of unnecessary light and heat exposure, keeping the lights off and/or the garments covered whenever you aren't actively photographing.
The Textile Specialty Group's wiki describes several different support methods for 3D textile artifacts and may include some useful options. It also has some advice for dressing a mannequin. Two C2CC resources on this topic are Mounting Garments for Display and Much Ado about Mannequins. Both focus on display rather than photography, but offer information about customizing mounts that may be relevant to your situation.
Hope this helps, please let me know if you have further questions.
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Rebecca Smyrl
Connecting to Collections Care Monitor
Assistant Conservator for Special Collections
UNC Chapel Hill Libraries
Chapel Hill NC
(919) 962-4250
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