Unfortunately, no. That wouldn't be permitted. If all they wanted was photos of steampunk attire, they could simply use google for that. Honestly, most questions you have about what constitutes an acceptable entry can be answered by just reading the rules. This is taken straight from the blurb on the contest page.
Quote:
- Entries must be created in a simple, Gaia-compatible web-based format and
drawn on the provided template. Template may not be cropped.
No screenshots, copy/pasted images, photos or references are allowed. Hand-drawn entries may be submitted if they are drawn directly on the template and follow all other rules for entry.