Welcome to APC, Les. You are not going to be able to find a job doing much of anything with 300 hours in the present market. Your best bet is to get the FAA Certified Flight Instructor (CFI), Instrument Instructor (CFII), Multiengine Instructor (MEI) certifications and find a job teaching people to fly. Not that anyone wants these tickets, it's just that unless you have a ton of money to use buying your flight hours most people have to earn the flight time and this is how most pilots do it. You mentioned some of the entry level commercial jobs and it is true that certain jobs only require about 500 hours to start. Aerial tours, skydiver flying, banner tow and pipeline patrol are a few of those jobs. However you are almost certainly not going to be able to find one of those jobs where your girlfriend lives, and even if you do these jobs are often seasonal and slow a lot of the time.
So, seriously consider getting the flight tickets to enable you to teach. The side benefit of adding the teaching certs is they make you a better pilot and make your resume look good so that when you get to about 1300 hours, which is the starting point for Part 135 jobs, you are competitive. With 300 hours you cannot fly Part 135 because only a few operations have permits allowing low time pilots (500 is the lowest hour figure), and almost none of those jobs are hiring at that number even though it is legal. Your best bet is to teach and with some luck there is a place to do it near your girlfriend's house. It will be expensive getting those tickets though.
A few years ago there was a shortage of entry level pilots in the US and the regionals did hire pilots with as little as 400 hours for a while. There were a bunch of problems with that, such as that almost nobody can keep up with a jet having so little flight experience, and they tended to drop out of training which is very bad for a resume. At any rate the hiring mins for regional jobs now hover around 1000 hours total and about 250 multiengine. That would be the low end of it, and the better jobs have higher minimums- say 1500 hours and about 500 multiengine. In addition, Congress is going to raise the minimum for regional airline pilots to 1500 hours anyway, so the point is moot.
The typical path for new pilots is to teach for a few years (2-3) to get to Part 135 minimums, then fly night freight or charter in a Part 135 operation for a couple more years, then apply to regional airlines and see what they can get with about 2000 hours. Good luck. The weather is warm here.