You're going to need to acclimate your legs to 800-pace work. I recommend starting with shorter race-pace intervals (easier workouts) and building to longer ones (harder workouts).
You have time for about 6 good workouts between now and then. 4 of them should be entirely 800m pace, and this would be a good progression:
16 x 100m @ 800m goal pace w/ 100m slow jog recovery (at least 3 days before the next 800m goal pace workout)
8 x 200m @ 800m goal pace w/ 200m slow jog recovery (at least 4 days before the next 800m goal pace workout)
2 x (4 x 300m @ 800m goal pace) w/ 100m slow jog recovery between reps and 400m walk/jog recovery between sets (at least 6 days before the next 800m pace workout)
3 x (200-400-200-100) w/ 100m slow jog recovery between reps and 400m walk/jog (at least 9 days before race day) (you will probably fall off pace in this workout, and that's fine)
Your other couple workouts right now should be multi-paced, things like 400-800-1200-1600-1200-800-400 at mile-5k-10k-tempo-10k-5k-mile effort all w/ 60s-90s recovery or 2 x mile @ tempo pace, 2 x 800 @ 5k pace, 2 x 400 @ mile pace, 2 x 200m hard all w/ 60-90s recovery.
This may all be a bit too much for someone who hasn't done a lot of 800m-pace work before. If it is, you can drop a workout (probably the 300m workout), or drop about 25% of the reps from any workout. Whether you do the full slate and volume of the workouts or not, it's just easy recovery mileage and strides on your non-workouts days between now and race day.
Good luck!