I got it from a shop on etsy but when I tried to find it now, I couldn't. Stripper supply stores are another good spot. But amazon should work, here's a link:
I'm a fairly muscular rock climber, so I can totally relate to this. Muscles are not inherently masculine, and wearing the right clothes can totally hide them if you want (but there's really no need to). I've found that tight see through mesh shirts (see link below) totally hide muscles and look super cute.
As for skirts, you can find pantyhose or leggings to wear under them that should hide any cuts and bruises. In my opinion though, cuts and bruises have nothing to do with being feminine.