I don't mind the bump, I had missed this one in the past.
If you're advertising this as a research/educational project, I bet you could get someone for $40-$50/hr. Instead of offering an hourly rate, I might offer a flat payment of $200 or $250 for an afternoon. I think a gal would be more willing to "work" as an actress for a seemingly legit video compared to posing for some horny guy's personal pleasure.
There's some
great information (and even better photos) from
dst6. Check out this thread:
https://forum.oneclickchicks.com/showthread.php?t=84501