is there a crypto gambling site that currently offers this kind of service?
There's none afaik, the closest you could get from spending way too much is to self exclude but that won't help since it's easy to create an account with other sites.
Escrows here may not into gambling but if their service is used I think they'll do it. I don't think the list of escrows on that thread will ruin their reputation and if I were the up into the challenge I'd hire the trusted and active user. Well, yeah as I propose it's better if we are the one who'll control our urges to gamble rather some intermediaries who meddle on our way to discipline ourselves. They might do the trick but I guess it's not for long.
I agree there's always some escrows willing to do it as long as certain conditions are met and I remember seeing a few gamblers do it before but it's scary if they suddenly became inactive.
One solid alternative to limited escrows would be using timelock to force your Bitcoins to confirm at a specific time.