That sounds like the original strings. I've played with several set ups in it in the past. I found it a pleasant racket to play with at higher tensions, but that's just my preference.
Go at 58 with poly's and 65 with multi's.
Just give it a try with the current set up, let a good stringer check the DT on it and go from there.
2x MAX 200G PRO, Nat.Gut/Ferry Force Super Touch at 58 lbs.