Nowt wrong with partners suggesting new things at all. My DH and I have both grown together as a sexual partnership because of it. We also both feel under no pressure to do as suggested, 'two ticks in the box' as we'd say 
So, this is truly what YOU want to do for YOU, you need to make sure you're safe.
You'll need to go on whatever you chosen site is and vet those you're meeting as best you can, maybe try a few meets without sex on the cards so you can judge the others, but do so in a public place and keep safe.
Just as important though, you need to think about what you'll do and what's out of bounds. You need to be sure that you can say no at any point without feeling silly, guilty or frightened to. Everyone has their line in different places so you need to be clear on yours and theirs.
Often the fantasy becomes less satisfying in reality as attraction isn't there or others are out to take pleasure, not give it.
Last of all, think about how you'd feel about yourself if you did, are you really this sort of person?