You won't know how the masseur will respond to your requesting sex until you discuss it with him. You might want to decide whether or not bringing up sex is worth potentially damaging your 8-year relationship (and on the flip side - if not addressing this desire and keeping things as they are is worth potential missed opportunities) . I've known masseurs who insist that they are not escorts and refuse to cross some line. They might allow MT and perform an HE, for example, but would be offended if a client suggested further sexual activity.
I agree with the idea of indirectly bringing up sex, as was mentioned earlier (e.g., asking if he ever hooks up with clients, asking about his opinion on masseurs who provide full service). If he were to take offense, you wouldn't have to claim it as a personal request. I also recognize that I worry too much about offending people at times, which has colored my post, and that simply asking him directly might suffice. I recently asked a masseur if he could remove my drape. With a concerned look, he asked "Why?". I was so embarrassed by this mild conflict, that I'll likely never return to him (even though the massage was solid). Your masseur has been giving you HJs for the past 8 years, however, so it's not like you're going from 0 to 100.