Perhaps a kit of 2kv caps like this offering from 'zon will get you close enough. I find that a little sorting with a decent meter will often find "in between" values.
https://www.amazon.com/dp/B00DDJQAAO?psc=1
How would one substitute the distributed cap in k-4... multiple caps and resistors? Perhaps 3 27k or 33k in series with 4 1000 uuf caps to ground.
not affiliated,
jr