Sorry for your loss, OP.
I echo other comments about not taking decisions when you are so emotionally vulnerable.
Should you decide to take a prossie, it should be someone you have punted multiple times, and not just for 30 or 60 minute sessions, but for longer sessions, dinners etc to make sure you enjoy the company the conversation etc.
Do your homework on the laws and customs of the place you'll be visiting. There have been cases of (legitimate) Western couples arrested in shirty countries because they weren't married. If your ages and races are too different, you will stand out, especially in some places where interracial couples are rare and/or frowned upon.
And you'll need to be comfortable with the risks to your privacy. In the UK you can probably check in at a hotel with a fake name if you pay cash. Abroad you typically have to show your passport. So she'll know your real name. She can look you up on Facebook Google or whatever. She might go through your documents and stuff while you are sleeping or in the bathroom. What if she were to ever blackmail you?
Maybe you could fly separately and get two separate rooms in the same hotel to reduce privacy risks.
Don't take this the wrong way, but the real risk I see is that of EAS, especially because you are so vulnerable now. Do bear in mind that, no matter how much chemistry you think you have, the girl you might take on holiday is a prossie who rents access to her cavities for money. Do you remember that disgusting, fat bald and smelly colleague you couldn't stand? She fucked him. And your annoying neighbour? Picture him grunting on top of her while he gives her a good pounding...
I always wondered to what extent some of the punters taking prossies on dinner "dates" and holidays want companionship, and to what extent they are looking for some delusional idealised version of "romance". I don't mean to offend you, I'm just pointing out what I think the risks could be, since you asked for advice. Have you watched the Escorts documentary on Netflix? If I remember well, there's a part where the girl gets booked for an overnight and says to the camera something like : of course he has a crush on me, he doesn't just want to shag me, otherwise why book an overnight?
Also, long bookings can be tiring for the girl as she has to "act" for much longer. I remember a girl telling me that many of her regulars book her for dinner dates overnight etc, which are less physically tiring but more mentally tiring as she has to put on her "show" for much longer.