5-8 X 800 @ 8k pace (2 sec a lap slower than 5k pace), 200 rest, do your last one at 5k pace.
Number is dependedant on your weekly mileage and relative experience with track workouts. About 8% of your weekly mileage in intervals of this speed is about right.
5=30 mpw
6-7=40 mpw
7-8 = >50 mpw
If like me you raced last night (most of us did), this is not a good workout to do, so you have a few options if you still want to come.
You could provide company to a runner slower than you, who might not otherwise have a workout partner.
You could do 8×200 followed by a longish 30 min cool down
You could just go for an easy run, maybe in the woods.