All letters to the Chinese are premium except A, E, I, O, U, V. Without knowing any of the facts, I'd say go for it, if it's a .com. Chinese premium 4L .com are selling at $2200 or thereabouts, now.
I think I read somewhere recently the 3 char .com are selling for around $40k. Probably more in China. It might be over $100k in China. Please note. I am not an expert in 3 char .com so don't follow the market that closely. I'd recommend you consult the domain broker Giuseppe Graziano at his company GGRG.COM. He is also a member at NamePros. He is well tuned-in to this market.
There's only 6 domains with this letters: KRS.com, KSR.com, RKS.com, RSK.com, SKR.com and SRK.com
Since all of them don't have letters that are toxic for Chinese they will be valuable.
As @stub explained price can be anywhere from 30-40K to 100K, depending on the owner, his need/wish to sell and who will contact him. If it end user and owner doesn't want to sell, price can be higher, if it lowball reseller and owner need money urgently - price can be lower.