He rarely, if ever, gives me oral. I don’t think he’s comfortable doing it. He likes getting sucked off but it’s not the be all and end all for him.
He’s really into the visual aspect, so likes spectating himself penetrating me, or using toys on me.
I did fool around with a woman, many, many years ago with his blessing. So I think there’s maybe hope that I could explore this avenue.
Next time we’re taking about sex stuff, I’ll see where it goes. Wish me luck!
I think you have your opening, right there then 
When the moment is right, maybe mention how it’s played on your mind, and you wished things had gone a little further, how it turned you on, focus on that and gauge the reaction. Leave it at that and maybe a later time take it a little further saying you’re mind has wandered to fantasizing how it would have been to have gave her oral or taking her to orgasm etc., after you’d talked about it.
You won’t need luck, I’m sure you’ll read the signs and know how far to take the convo around it.