No easy route I'm afraid.
Wouldn't think loans would be likely. Borrowing / gifting from parents or Grandparents its still going to be the majority of funding for most CPL(H) students. Scholarships only really exist from Bristow and they are very few. Don't count on those, but they do get advertised very occasionally and a few lucky individuals get chosen and trained. Haven't seen one advertised for a while, but speak to CastleAir perhaps who are their training provider.
Integrated is fine and works quickly, but you graduate with less hours in total. It tends to attract very dedicated professional pilots that want to go into industry. But if you are dedicated, you could do a modular course intensively in a little longer. And come out with more P1 (Command time) in your logbook, which can be really useful for going on to be a Flying Instructor (first job) or going for the Instrument Rating - Needed for most of those roles you are looking for.
Not sure you can currently get a UK licence overseas. It has been possible, but haven't heard of an ATO doing that for a while. Probably stick to the UK. Helicentre, CastleAir, HeliAir, Helicopter Services at White Waltham, Elite at Goodwood. There will be others, but those are probably the biggest. Lots of people will have opinions on the merits or otherwise of each of those. There will be lots of opinions - You would have to visit each school and see what you think.
Getting that first job is always going to be difficult. The employment rate for graduates does seem to have been very good. The North Sea has been taking on most of the pilots that wanted employment in the offshore windfarm or energy sector. Quite a few Air Ambulances going multi-crew, so new co-pilots being taken on there also, but there are limited flying hours and career progression. Some opportunities also in VIP flying, but still quite a few will pay for more training to become a Flying Instructor and teach the next generation. A good way to build hours, but the cost of the course is high, and you are probably as well, just paying a little bit more to get your Instrument Rating.
Job market in the North Sea has been fairly turbulent lately, but there is still work to be had and who knows how the political climate will change the offshore fortunes. The honest difficulty is that you will br training now and committing to a path, that will see you qualified in the summer of 2028, and nobody knows what the market will look like then. I think many predict a continuing pilot shortage with lots retiring and not many coming through. But it would be a risk. You've done well to save up money, and you could if you were lucky, double your salary as an entry level pilot, and triple it within 3 or 4 years, so there is a genuine return on investment, but primarily for those that pay the full £150,000 to get an IR and go onto the North Sea.
Keep looking out for the sponsorship notices that get well advertised if they happen. Good luck with following your ambitions and I hope it works out.