A possible image resource is Icon Generator from Axialis. This free program works with licensed and free icon sets in vector format. You can set color schemes and add corner overlays. Icons can be output as bit mapped images in formats compatible with LabVIEW.
If you like icons with depth (as opposed to the current flat style), a good collection of PNG images is the Crystal Project set (16x16 https://github.com/thecodingmachine/crystal-project and https://store.kde.org/content/show.php?content=60475). I've seen 16x16, 22x22, 24x24, 32x32, 48x48, 64x64 and 128x128 pixel sets. Another similarly styled 16x16 pixel set of PNG images is available at http://www.famfamfam.com/lab/icons/silk/.
